Added error checking for OBJ_create

fixes segmentation fault in case of not enough memory for object creation

CLA: trivial

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3157)
diff --git a/crypto/objects/obj_dat.c b/crypto/objects/obj_dat.c
index f37e947..2f86cd5 100644
--- a/crypto/objects/obj_dat.c
+++ b/crypto/objects/obj_dat.c
@@ -691,6 +691,8 @@
 
     /* Convert numerical OID string to an ASN1_OBJECT structure */
     tmpoid = OBJ_txt2obj(oid, 1);
+    if (tmpoid == NULL)
+        return 0;
 
     /* If NID is not NID_undef then object already exists */
     if (OBJ_obj2nid(tmpoid) != NID_undef) {