lvm2: don't use `-normal` suffix for non-SELinux variants

lvm2: don't use `-normal` suffix for non-SELinux variants

This was probably a work-around for an issue with dependencies which
was fixed by
https://github.com/openwrt/openwrt/commit/988ed0080284903d1fe4851c5ae8f1238bc61da2

Remove it as all other packages with `-selinux` variants do provide
a non-SELinux-variant without any suffix and that works now, see
procd vs. procd-selinux
busybox vs. busybox-selinux

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
(cherry picked from commit 43597b918a43f431f9f328aa07904c920832a435)