perf script: Share code and output format for uregs and iregs output

perf script: Share code and output format for uregs and iregs output

The iregs output was missing the newline at end as well as the leading
ABI output. This made it hard to compare the iregs and uregs values.
Instead, use a single function to output the register values and use it
for both, iregs and uregs, to ensure the output is consistent.

Before:

  perf  7049 [-01]  1343.354347:          1 cycles:ppp:
        ffffffffa7bc21ce perf_event_exec+0x18e (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7ead3 setup_new_exec+0xf3 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7cd7be5 load_elf_binary+0x395 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7e540 search_binary_handler+0x80 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f1aa __do_execve_file.isra.13+0x58a (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f561 do_execve+0x21 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f596 __x64_sys_execve+0x26 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7a041cb do_syscall_64+0x5b (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa840008c entry_SYSCALL_64+0x7c (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
    AX:0x80000000    BX:0x0    CX:0x0    DX:0x7    SI:0xf    DI:0x286    BP:0xffff95bc8213a460    SP:0xffffacbf0ba97d18    IP:0xffffffffa7bc21cd FLAGS:0x28e    CS:0x10    SS:0x18    R8:0x2    R9:0x21440   R10:0x33816fb3b8c   R11:0x1   R12:0xffff95bc8213a460   R13:0xffff95bc8213a400   R14:0xffff95bc8213a400   R15:0x1  ABI:2    AX:0xffffffffffffffda    BX:0xffffffffffffffff    CX:0x7f84ad85798b    DX:0x560209699d50    SI:0x7ffe2c7a6820    DI:0x7ffe2c7a8c9b    BP:0x7ffe2c7a20d0    SP:0x7ffe2c7a2058    IP:0x7f84ad85798b FLAGS:0x206    CS:0x33    SS:0x2b    R8:0x7ffe2c7a2030    R9:0x7f84ae55f010   R10:0x8   R11:0x206   R12:0xffffffffffffffff   R13:0xffffffffffffffff   R14:0xffffffffffffffff   R15:0xffffffffffffffff

  perf  7049 [-01]  1343.354363:          1 cycles:ppp:
        ...

After:

  perf  7049 [-01]  1343.354347:          1 cycles:ppp:
        ffffffffa7bc21ce perf_event_exec+0x18e (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7ead3 setup_new_exec+0xf3 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7cd7be5 load_elf_binary+0x395 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7e540 search_binary_handler+0x80 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f1aa __do_execve_file.isra.13+0x58a (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f561 do_execve+0x21 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f596 __x64_sys_execve+0x26 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7a041cb do_syscall_64+0x5b (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa840008c entry_SYSCALL_64+0x7c (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
    ABI:2    AX:0x80000000    BX:0x0    CX:0x0    DX:0x7    SI:0xf    DI:0x286    BP:0xffff95bc8213a460    SP:0xffffacbf0ba97d18    IP:0xffffffffa7bc21cd FLAGS:0x28e    CS:0x10    SS:0x18    R8:0x2    R9:0x21440   R10:0x33816fb3b8c   R11:0x1   R12:0xffff95bc8213a460   R13:0xffff95bc8213a400   R14:0xffff95bc8213a400   R15:0x1
    ABI:2    AX:0xffffffffffffffda    BX:0xffffffffffffffff    CX:0x7f84ad85798b    DX:0x560209699d50    SI:0x7ffe2c7a6820    DI:0x7ffe2c7a8c9b    BP:0x7ffe2c7a20d0    SP:0x7ffe2c7a2058    IP:0x7f84ad85798b FLAGS:0x206    CS:0x33    SS:0x2b    R8:0x7ffe2c7a2030    R9:0x7f84ae55f010   R10:0x8   R11:0x206   R12:0xffffffffffffffff   R13:0xffffffffffffffff   R14:0xffffffffffffffff   R15:0xffffffffffffffff

  perf  7049 [-01]  1343.354363:          1 cycles:ppp:
        ...

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181107223437.9071-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>