Revert "drm/amdgpu: change SH MEM alignment mode for gfx10"

This reverts commit b74fb888.
Revert the auto alignment mode set of SH MEM config, as it will result
to OCL Conformance Test fail.

Signed-off-by: Likun Gao <Likun.Gao@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>