mfd: fix build failures in recently added ab5500 code

These files had implicit dependencies on modular support
which now show up as build failures with the module cleanup
work merged to mainline.

Reported-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --cc drivers/mfd/ab5500-core.c
Simple merge

diff --cc drivers/mfd/ab5500-debugfs.c
Simple merge