x86/setup: Cleanup crashkernel reservation functions

x86/setup: Cleanup crashkernel reservation functions

* Shorten variable names
* Realign code, space out for better readability

No code changed:

  # arch/x86/kernel/setup.o:

   text    data     bss     dec     hex filename
   4543    3096   69904   77543   12ee7 setup.o.before
   4543    3096   69904   77543   12ee7 setup.o.after

md5:
   8a1b7c6738a553ca207b56bd84a8f359  setup.o.before.asm
   8a1b7c6738a553ca207b56bd84a8f359  setup.o.after.asm

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Chao <chaowang@redhat.com>
Cc: jerry_hoemann@hp.com
Link: http://lkml.kernel.org/r/1445246268-26285-4-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>