x86, vmlinux.lds: unify .exit.* and .init.ramfs

[ Impact: cleanup ]

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Tim Abbott <tabbott@MIT.EDU>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1240991249-27117-11-git-send-email-sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>