ARM: UniPhier: leave the last element of boot_device_table empty

Checking if the pointer is NULL would be easier to know the tail
of the boot_device_table[] array.
For clarification, add the /* sentinel */ comment.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

arch/arm/cpu/armv7/uniphier/cmd_pinmon.c

@@ -19,7 +19,7 @@ static int do_pinmon(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 
 	puts("Boot Mode Pin:\n");
 
-	for (i = 0; strlen(boot_device_table[i].info); i++)
+	for (i = 0; boot_device_table[i].info; i++)
 		printf(" %c %02x %s\n", i == mode_sel ? '*' : ' ', i,
 		       boot_device_table[i].info);
 

arch/arm/cpu/armv7/uniphier/ph1-pro4/boot-mode.c

@@ -45,7 +45,7 @@ struct boot_device_info boot_device_table[] = {
 	{BOOT_DEVICE_NONE, "Reserved"},
 	{BOOT_DEVICE_NONE, "Reserved"},
 	{BOOT_DEVICE_NONE, "Reserved"},
-	{BOOT_DEVICE_NONE, ""}
+	{ /* sentinel */ }
 };
 
 int get_boot_mode_sel(void)