drm/amd/display: Add DC build_id to determine build type

[why]
Sometimes there are indications that the incorrect driver is being
loaded in automated tests. This change adds the ability for builds to
be tagged with a string, and picked up by the test infrastructure.

[how]
dc.c will allocate const for build id, which is init-ed with default
value, indicating production build. For test builds, build server will
find/replace this value. The test machine will then verify this value.
Signed-off-by: Jun Lei <Jun.Lei@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -60,6 +60,7 @@
 #define DC_LOGGER \
 	dc->ctx->logger
 
+const static char DC_BUILD_ID[] = "production-build";
 
 /*******************************************************************************
  * Private functions
@@ -758,6 +759,8 @@ struct dc *dc_create(const struct dc_init_data *init_params)
 
 	dc->config = init_params->flags;
 
+	dc->build_id = DC_BUILD_ID;
+
 	DC_LOG_DC("Display Core initialized\n");
 
 

drivers/gpu/drm/amd/display/dc/dc.h

@@ -315,6 +315,8 @@ struct dc {
 	struct compressor *fbc_compressor;
 
 	struct dc_debug_data debug_data;
+
+	const char *build_id;
 };
 
 enum frame_buffer_mode {