MIPS: ralink: add missing SZ_1M multiplier

On RT5350 the memory size is set to Bytes and not MegaBytes due to a missing
multiplier.
Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Patchwork: https://patchwork.linux-mips.org/patch/5378/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/ralink/of.c

@@ -88,7 +88,7 @@ void __init plat_mem_setup(void)
 	__dt_setup_arch(&__dtb_start);
 
 	if (soc_info.mem_size)
-		add_memory_region(soc_info.mem_base, soc_info.mem_size,
+		add_memory_region(soc_info.mem_base, soc_info.mem_size * SZ_1M,
 				  BOOT_MEM_RAM);
 	else
 		detect_memory_region(soc_info.mem_base,