global: Migrate CONFIG_MAX_MEM_MAPPED to CFG

Perform a simple rename of CONFIG_MAX_MEM_MAPPED to CFG_MAX_MEM_MAPPED

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/xtensa/include/asm/config.h b/arch/xtensa/include/asm/config.h
index 21b334b..268c568 100644
--- a/arch/xtensa/include/asm/config.h
+++ b/arch/xtensa/include/asm/config.h
@@ -14,7 +14,7 @@
  * restricting used physical memory to the first 128MB.
  */
 #if XCHAL_HAVE_PTP_MMU
-#define CONFIG_MAX_MEM_MAPPED (128 << 20)
+#define CFG_MAX_MEM_MAPPED (128 << 20)
 #endif
 
 #endif