mesa: include util/macros.h in format_fallback.c

To get definition of unreachable() macro.

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/mesa/main/format_fallback.py

@@ -87,6 +87,7 @@ def get_rgbx_to_rgba_map(formats):
 
 TEMPLATE = Template(COPYRIGHT + """
 #include "formats.h"
+#include "util/macros.h"
 
 /**
  * For an sRGB format, return the corresponding linear color space format.