FIx memory leak in x509_attr_descr_from_numericoid;

Signed-off-by: Agathiyan Bragadeesh <agathiyan.bragadeesh2@arm.com>
diff --git a/library/x509_create.c b/library/x509_create.c
index 80beff2..8ce3584 100644
--- a/library/x509_create.c
+++ b/library/x509_create.c
@@ -150,6 +150,7 @@
     }
 
     mbedtls_free(oid->p);
+    mbedtls_free(oid);
     if (cur->oid == NULL) {
         return NULL;
     }