s390: replace remaining strict_strtoul() with kstrtoul()

Replace the last two strict_strtoul() with kstrtoul().

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index e9fadb0..2bc0803 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -1299,7 +1299,7 @@
 
 	if (!name || *name != 'r')
 		return -EINVAL;
-	if (strict_strtoul(name + 1, 10, &offset))
+	if (kstrtoul(name + 1, 10, &offset))
 		return -EINVAL;
 	if (offset >= NUM_GPRS)
 		return -EINVAL;