MIPS: ath79: Increase max memory limit to 256MByte

At least QCA955x can handle up to 256MBytes.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Cc: linux-mips@linux-mips.org
Cc: Gabor Juhos <juhosg@openwrt.org>
Cc: Helmut Schaa <helmut.schaa@googlemail.com>
Patchwork: https://patchwork.linux-mips.org/patch/8738/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/ath79/common.h

@@ -17,7 +17,7 @@
 #include <linux/types.h>
 
 #define ATH79_MEM_SIZE_MIN	(2 * 1024 * 1024)
-#define ATH79_MEM_SIZE_MAX	(128 * 1024 * 1024)
+#define ATH79_MEM_SIZE_MAX	(256 * 1024 * 1024)
 
 void ath79_clocks_init(void);
 unsigned long ath79_get_sys_clk_rate(const char *id);