patch 8.0.1576: Perl VIM::Buffers() does not find every buffer

Problem:    Perl VIM::Buffers() does not find every buffer.
Solution:   Also find unlisted buffer by number or name. (Chris Weyl,
            closes #2692)
diff --git a/src/version.c b/src/version.c
index c47cf6b..65b5d2d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -767,6 +767,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1576,
+/**/
     1575,
 /**/
     1574,