Make use of write enable flag for mem bo map

Make use of write enable flag for mem bo map

Use drm/intel optimization for mem bo mapping in case of read or write.
So we could be possibly waiting less.

This also adds 'map_flags' check in clEnqueueMapBuffer/clEnqueueMapImage
for actual read or write mapping.

But currently leave clMapBufferIntel untouched which might break ABI/API.

v2: Fix write_map flag in clEnqueueMapBuffer/clEnqueueMapImage.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Reviewed-by: "Guo, Yejun" <yejun.guo@intel.com>
Reviewed-by: Zhigang Gong <zhigang.gong@linux.intel.com>