compositor-drm: Print DRM FB pixel format of the view in human-friendly form

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>

libweston/compositor-drm.c

@@ -1640,6 +1640,8 @@ drm_fb_get_from_view(struct drm_output_state *state, struct weston_view *ev)
 		}
 	}
 
+	drm_debug(b, "\t\t\t[view] view %p format: %s\n",
+		  ev, fb->format->drm_format_name);
 	drm_fb_set_buffer(fb, buffer);
 	return fb;
 }