s390/boot: Replace strncpy() with strscpy()

Replace the last 2 usages of strncpy() in s390 code with strscpy().

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

Author: Vasily Gorbik

arch/s390/boot/ipl_parm.c

@@ -309,7 +309,7 @@ void parse_boot_command_line(void)
 		if (!strcmp(param, "bootdebug")) {
 			bootdebug = true;
 			if (val)
-				strncpy(bootdebug_filter, val, sizeof(bootdebug_filter) - 1);
+				strscpy(bootdebug_filter, val);
 		}
 		if (!strcmp(param, "quiet"))
 			boot_console_loglevel = CONSOLE_LOGLEVEL_QUIET;

arch/s390/boot/printk.c

@@ -158,7 +158,7 @@ static noinline char *strsym(char *buf, void *ip)
 
 	p = findsym((unsigned long)ip, &off, &len);
 	if (p) {
-		strncpy(buf, p, MAX_SYMLEN);
+		strscpy(buf, p, MAX_SYMLEN);
 		/* reserve 15 bytes for offset/len in symbol+0x1234/0x1234 */
 		p = buf + strnlen(buf, MAX_SYMLEN - 15);
 		strcpy(p, "+0x");