MIPS: Alchemy: Fix unchecked kstrtoul return value

enabled __must_check logic triggers a build error for mtx1 and gpr
in the prom init code.  Fix by checking the kstrtoul() return value.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/6574/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/alchemy/board-gpr.c b/arch/mips/alchemy/board-gpr.c
index 9edc35f..acf9a2a 100644
--- a/arch/mips/alchemy/board-gpr.c
+++ b/arch/mips/alchemy/board-gpr.c
@@ -53,10 +53,8 @@
 	prom_init_cmdline();
 
 	memsize_str = prom_getenv("memsize");
-	if (!memsize_str)
+	if (!memsize_str || kstrtoul(memsize_str, 0, &memsize))
 		memsize = 0x04000000;
-	else
-		strict_strtoul(memsize_str, 0, &memsize);
 	add_memory_region(0, memsize, BOOT_MEM_RAM);
 }
 
diff --git a/arch/mips/alchemy/board-mtx1.c b/arch/mips/alchemy/board-mtx1.c
index 9969dba..25a59a2 100644
--- a/arch/mips/alchemy/board-mtx1.c
+++ b/arch/mips/alchemy/board-mtx1.c
@@ -52,10 +52,8 @@
 	prom_init_cmdline();
 
 	memsize_str = prom_getenv("memsize");
-	if (!memsize_str)
+	if (!memsize_str || kstrtoul(memsize_str, 0, &memsize))
 		memsize = 0x04000000;
-	else
-		strict_strtoul(memsize_str, 0, &memsize);
 	add_memory_region(0, memsize, BOOT_MEM_RAM);
 }