MIPS: Alchemy: Add return value check for strict_strtoul()

arch/mips/alchemy/devboards/prom.c: In function 'prom_init':
arch/mips/alchemy/devboards/prom.c:60: error: ignoring return value of
'strict_strtoul', declared with attribute warn_unused_result

Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/1761/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/alchemy/devboards/prom.c

@@ -54,10 +54,9 @@ void __init prom_init(void)
 
 	prom_init_cmdline();
 	memsize_str = prom_getenv("memsize");
-	if (!memsize_str)
+	if (!memsize_str || strict_strtoul(memsize_str, 0, &memsize))
 		memsize = ALCHEMY_BOARD_DEFAULT_MEMSIZE;
-	else
-		strict_strtoul(memsize_str, 0, &memsize);
+
 	add_memory_region(0, memsize, BOOT_MEM_RAM);
 }