armv7: rename cache related CONFIG flags

Replace the cache related CONFIG flags with more meaningful
names. Following are the changes:

CONFIG_L2_OFF	     -> CONFIG_SYS_L2CACHE_OFF
CONFIG_SYS_NO_ICACHE -> CONFIG_SYS_ICACHE_OFF
CONFIG_SYS_NO_DCACHE -> CONFIG_SYS_DCACHE_OFF

Signed-off-by: Aneesh V <aneesh@ti.com>
V2:
 * Changed CONFIG_L2_OFF -> CONFIG_SYS_NO_L2CACHE
V4:
 * Changed all three flags to the final names suggested as above
   and accordingly changed the commit message
diff --git a/include/configs/assabet.h b/include/configs/assabet.h
index 5cd1836..dc9bd88 100644
--- a/include/configs/assabet.h
+++ b/include/configs/assabet.h
@@ -38,7 +38,7 @@
 
 #undef CONFIG_USE_IRQ
 /* we will never enable dcache, because we have to setup MMU first */
-#define CONFIG_SYS_NO_DCACHE
+#define CONFIG_SYS_DCACHE_OFF
 
 #define CONFIG_CMDLINE_TAG	 1	/* enable passing of ATAGs      */
 #define CONFIG_SETUP_MEMORY_TAGS 1