dmaengine: add dmaengine_prep_dma_sg() helper
dmaengine: add dmaengine_prep_dma_sg() helper

This was only prep API which didnt have an helper

Signed-off-by: Vinod Koul <5cf69c63beb17bf38d63aa0e923ee8256af0e205@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs