There were no reports about the previous warning for FPU exceptions in the
kernel, so make it a die() now.

Also improve the error messages slightly.
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>