shared/gatt-client: Fix discover_primary_cb()

Fix the handling of primary services discovery failure.

(cherry picked from commit cdc2355b608d8950998cbe99023bb58792883592)

Change-Id: I8100cee0142525b779dd6f9f3243f983e5636290
diff --git a/src/shared/gatt-client.c b/src/shared/gatt-client.c
index 4386692..84145e7 100644
--- a/src/shared/gatt-client.c
+++ b/src/shared/gatt-client.c
@@ -1052,11 +1052,14 @@
 					"Primary service discovery failed."
 					" ATT ECODE: 0x%02x", att_ecode);
 		/* Reset error in case of not found */
-		if (BT_ATT_ERROR_ATTRIBUTE_NOT_FOUND) {
+		switch (att_ecode) {
+		case BT_ATT_ERROR_ATTRIBUTE_NOT_FOUND:
 			success = true;
 			att_ecode = 0;
+			goto secondary;
+		default:
+			goto done;
 		}
-		goto secondary;
 	}
 
 	if (!result || !bt_gatt_iter_init(&iter, result)) {