ARC: Don't memzero twice in dma_alloc_coherent for __GFP_ZERO
ARC: Don't memzero twice in dma_alloc_coherent for __GFP_ZERO

alloc_pages_exact() get gfp flags and handle zero'ing already

And while it, fix the case where ioremap fails: return rightaway.

Signed-off-by: Vineet Gupta <af669d95a4c0de051445d4cafdbb2c5c4a2838be@synopsys.com>

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