m68k/kernel: replace strncpy() with strscpy()

Swapped out strncpy() for strscpy() in parse_uboot_commandline() while
copying to commandp. strscpy() makes sure the string is properly null-
terminated and gives a more useful return value so it's just a safer
choice overall.

Link: KSPP#90
Signed-off-by: Mohammad Mahdi Anbaraki <m.mahdianbaraki@gmail.com>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>

Author: binophism

arch/m68k/kernel/uboot.c

@@ -73,7 +73,7 @@ static void __init parse_uboot_commandline(char *commandp, int size)
 	uboot_cmd_end = sp[5];
 
 	if (uboot_cmd_start && uboot_cmd_end)
-		strncpy(commandp, (const char *)uboot_cmd_start, size);
+		strscpy(commandp, (const char *)uboot_cmd_start, size);
 
 #if defined(CONFIG_BLK_DEV_INITRD)
 	uboot_initrd_start = sp[2];