staging: sm750fb: Replace POKE32 and PEEK32 by inline functions

POKE32 and PEEK32 have been replaced by inlined functions poke32 and
peek32.
Having inline functions instead of macros help to get the correct
type-checking and avoid the possible precedence issues reported by
checkpatch.

Signed-off-by: Matthieu Simon <gmatthsim@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>