patch 8.1.1973: cannot build without the quickfix feature

Problem:    Cannot build without the quickfix feature.
Solution:   Remove #ifdef for qf_info_T.
diff --git a/src/version.c b/src/version.c
index 321da51..c9860ac 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1973,
+/**/
     1972,
 /**/
     1971,