[PATCH] cris: fix KSTK_EIP

cris KSTK_EIP looked for pt_regs at the right offset but from the wrong
place - forgotten ->thread_info

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>