Remove warnings from compilation of the s2892 with and without CBFS.

Remove warnings from compilation of the s2892 with and without CBFS.

I didn't try to remove "defined but not used" warnings because there are too
many ifdefs to be sure I wouldn't break something.

For shadowed variable declarations I renamed the inner-most variable.

The one in src/pc80/keyboard.c might need help.  I didn't change the
functionality but it looks like a bug.

I boot tested it on s2892 and abuild tested it.

Signed-off-by: Myles Watson <mylesgw@gmail.com>
Acked-by: Ronald G. Minnich <rminnich@gmail.com>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4240 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1