powerpc/fsl: enable verbose bug output

This debug option has no overhead other than a slight increase in
kernel size, and makes bug reports more useful.  While some end users
may prefer to save the space, as a default on a kernel config aimed
primarily at development on reference boards, it should be enabled.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>