arm, arm-kirkwood: disable l2c before linux boot

The decompressor expects the L2 cache to be disabled. This fixes booting
some kernels, which have CONFIG_ARM_PATCH_PHYS_VIRT enabled.

Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
Cc: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Wolfgang Denk <wd@denx.de>
diff --git a/arch/arm/cpu/arm926ejs/cache.c b/arch/arm/cpu/arm926ejs/cache.c
index ee90ab7..504f604 100644
--- a/arch/arm/cpu/arm926ejs/cache.c
+++ b/arch/arm/cpu/arm926ejs/cache.c
@@ -68,3 +68,12 @@
 {
 }
 #endif /* #ifndef CONFIG_SYS_DCACHE_OFF */
+
+/*
+ * Stub implementations for l2 cache operations
+ */
+void __l2_cache_disable(void)
+{
+}
+void l2_cache_disable(void)
+        __attribute__((weak, alias("__l2_cache_disable")));