mesa: remove support for GCC older than 3.3.0

GCC >=3.3 has been required since 9aa3aa71386394725ce88df463d6183f62777ee5

Signed-off-by: Timothy Arceri <t_arceri@yahoo.com.au>
Reviewed-By: Jose Fonseca <jfonseca@vmware.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
diff --git a/include/c99_compat.h b/include/c99_compat.h
index 429c601..e5d0ae4 100644
--- a/include/c99_compat.h
+++ b/include/c99_compat.h
@@ -114,11 +114,7 @@
 #  elif defined(__SUNPRO_C) && defined(__C99FEATURES__)
      /* C99 */
 #  elif defined(__GNUC__)
-#    if __GNUC__ >= 2
-#      define __func__ __FUNCTION__
-#    else
-#      define __func__ "<unknown>"
-#    endif
+#    define __func__ __FUNCTION__
 #  elif defined(_MSC_VER)
 #    if _MSC_VER >= 1300
 #      define __func__ __FUNCTION__