arm926ejs: cache: use __weak

Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>

arch/arm/cpu/arm926ejs/cache.c

@@ -99,7 +99,4 @@ void flush_cache(unsigned long start, unsigned long size)
 /*
  * Stub implementations for l2 cache operations
  */
-void __l2_cache_disable(void) {}
-
-void l2_cache_disable(void)
-	__attribute__((weak, alias("__l2_cache_disable")));
+__weak void l2_cache_disable(void) {}