util: limit gnu_printf format attribute to gcc >= 4.4.0

The gnu_printf format attribute was introduced in gcc 4.4.0
https://gcc.gnu.org/legacy-ml/gcc-help/2012-02/msg00225.html.

Use the printf format attribute on earlier versions of gcc and clang
(which claims to be gcc 4.2.1 in builtin defines) to fix the build with
gcc 4.2.1.

Fixes: 588a29f ("util: use gnu_printf format attribute")
Signed-off-by: Jonathan Gray <jsg@jsg.id.au>
Message-Id: <20210206100110.75228-1-jsg@jsg.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

util.h

@@ -13,10 +13,10 @@
  */
 
 #ifdef __GNUC__
-#ifdef __clang__
+#if __GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4)
-#define PRINTF(i, j)	__attribute__((format (printf, i, j)))
-#else
 #define PRINTF(i, j)	__attribute__((format (gnu_printf, i, j)))
+#else
+#define PRINTF(i, j)	__attribute__((format (printf, i, j)))
 #endif
 #define NORETURN	__attribute__((noreturn))
 #else