regulator: da9052: Include linux/of.h to fix build warning for of_match_ptr

Remove #ifdef CONFIG_OF guard so linux/of.h will be included when
!CONFIG_OF. This fixes build warnings when !CONFIG_OF.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>