Add vega12 to amd_asic_type enum and amdgpu_asic_name[].
Acked-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NHawking Zhang <Hawking.Zhang@amd.com>