patch 9.1.0536: filetype: zone files are not recognized

Problem:  filetype: zone files are not recognized
          (rpdprd)
Solution: Detect '*.zone' files as bindzone filetype

fixes: #14222

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index a3d8891..d6491be 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -121,7 +121,7 @@
     beancount: ['file.beancount'],
     bib: ['file.bib'],
     bicep: ['file.bicep', 'file.bicepparam'],
-    bindzone: ['named.root', '/bind/db.file', '/named/db.file', 'any/bind/db.file', 'any/named/db.file'],
+    bindzone: ['named.root', '/bind/db.file', '/named/db.file', 'any/bind/db.file', 'any/named/db.file', 'foobar.zone'],
     bitbake: ['file.bb', 'file.bbappend', 'file.bbclass', 'build/conf/local.conf', 'meta/conf/layer.conf', 'build/conf/bbappend.conf', 'meta-layer/conf/distro/foo.conf'],
     blade: ['file.blade.php'],
     blank: ['file.bl'],
diff --git a/src/version.c b/src/version.c
index ffbc13e..359605b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    536,
+/**/
     535,
 /**/
     534,