patch 8.1.0288: quickfix code uses cmdidx too often

Problem:    Quickfix code uses cmdidx too often.
Solution:   Add is_loclist_cmd(). (Yegappan Lakshmanan)
diff --git a/src/version.c b/src/version.c
index efc214c..82b7022 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    288,
+/**/
     287,
 /**/
     286,