kexec: return error number directly

This is a cleanup patch to make kexec more clear to return error number
directly.  The variable result is useless, because there is no other
function's return value assignes to it.  So remove it.

Link: http://lkml.kernel.org/r/1464179273-57668-1-git-send-email-mnghuan@gmail.com


Signed-off-by: Minfei Huang <mnghuan@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>