patch 9.1.0311: filetype: Some config files are not recognized

Problem:  Some config files are not recognized
Solution: Add some patterns for chktex, ripgreprc and ctags config
          files.

See: https://www.nongnu.org/chktex/
See: https://github.com/BurntSushi/ripgrep/blob/master/GUIDE.md#configuration-file
See: https://docs.ctags.io/en/latest/option-file.html#order-of-loading-option-files

closes: #14506

Signed-off-by: Wu, Zhenyu <wuzhenyu@ustc.edu>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index f17ac62..e3c98e6 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -308,6 +308,9 @@
 " CSDL
 au BufNewFile,BufRead *.csdl			setf csdl
 
+" Ctags
+au BufNewFile,BufRead *.ctags			setf conf
+
 " Cabal
 au BufNewFile,BufRead *.cabal			setf cabal
 
@@ -327,6 +330,9 @@
 " Chatito
 au BufNewFile,BufRead *.chatito			setf chatito
 
+" Chktex
+au BufRead,BufNewFile .chktexrc			setf conf
+
 " Chuck
 au BufNewFile,BufRead *.ck			setf chuck
 
@@ -1863,6 +1869,9 @@
 " Rexx
 au BufNewFile,BufRead *.rex,*.orx,*.rxo,*.rxj,*.jrexx,*.rexxj,*.rexx,*.testGroup,*.testUnit	setf rexx
 
+" Ripgrep rc
+au BufNewFile,BufRead {.,}ripgreprc			setf conf
+
 " R Help file
 if has("fname_case")
   au BufNewFile,BufRead *.rd,*.Rd		setf rhelp
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 89ccac9..7dc282f 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -162,7 +162,7 @@
     cobol: ['file.cbl', 'file.cob', 'file.lib'],
     coco: ['file.atg'],
     conaryrecipe: ['file.recipe'],
-    conf: ['auto.master', 'file.conf', 'texdoc.cnf', '.x11vncrc'],
+    conf: ['auto.master', 'file.conf', 'texdoc.cnf', '.x11vncrc', '.chktexrc', '.ripgreprc', 'ripgreprc', 'file.ctags'],
     config: ['configure.in', 'configure.ac', '/etc/hostname.file', 'any/etc/hostname.file'],
     confini: ['/etc/pacman.conf', 'any/etc/pacman.conf', 'mpv.conf', 'any/.aws/config', 'any/.aws/credentials', 'file.nmconnection'],
     context: ['tex/context/any/file.tex', 'file.mkii', 'file.mkiv', 'file.mkvi', 'file.mkxl', 'file.mklx'],
diff --git a/src/version.c b/src/version.c
index e30a1bc..f2d28ce 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    311,
+/**/
     310,
 /**/
     309,