smdk4412: disable CMA allocations for I9300 and N7100

Samsung labelled DMA_CMA as experimental and currently there are
issues with CMA MFC allocations failing which affects the video
recording and video playback. I9305 doesn't enforce CMA allocations
and hence disable them for I9300 and N7100 too.

Change-Id: Ie7bc0e4fd5089083bc559d97648abfb8b9046489
Conflicts:
	arch/arm/configs/cyanogenmod_i9300_defconfig