It was an enablement vehicle for MES 11 and was never
productized.  Remove it.

v2: drop additional checks in the GFX10 code.
v3: drop mes_api_def.h
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>