patch 9.0.1167: EditorConfig files do not have their own filetype

Problem:    EditorConfig files do not have their own filetype.
Solution:   Add the "editorconfig" filetype. (Gregory Anders, closes #11779)
diff --git a/src/version.c b/src/version.c
index 6bddfff..a218a71 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1167,
+/**/
     1166,
 /**/
     1165,