drm/amdgpu: Change the imprecise function name

The callback functions are used for SRIOV read/write instead
of just for rlcg read/write

Signed-off-by: Roy Sun <Roy.Sun@amd.com>
Reviewed-by: Zhou pengju <pengju.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>