[PATCH] kthread: convert arch/i386/kernel/apm.c

Convert i386 apm.c from kernel_thread(), whose export is deprecated, to
kthread API.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>