Fix code style issue in cert_write program

Signed-off-by: Waleed Elmelegy <waleed.elmelegy@arm.com>
diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 19215c9..8bee0a6 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.c
@@ -584,7 +584,8 @@
                 if ((subtype_value = strchr(q, ':')) != NULL) {
                     *subtype_value++ = '\0';
                 } else {
-                    mbedtls_printf("Invalid argument for option SAN: Entry should be separated by a colon\n");
+                    mbedtls_printf(
+                        "Invalid argument for option SAN: Entry should be separated by a colon\n");
                     goto usage;
                 }
                 if (strcmp(q, "RFC822") == 0) {