patch 9.1.0982: TI linker files are not recognized

Problem:  TI linker files are not recognized
Solution: inspect '*.cmd' files and detect TI linker files
          as 'lnk' filetype, include a lnk ftplugin and syntax
          script (Wu, Zhenyu)

closes: #16320

Signed-off-by: Wu, Zhenyu <wuzhenyu@ustc.edu>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_filetype.vim

@@ -2309,6 +2309,27 @@ func Test_cls_file()
   filetype off
 endfunc
 
+func Test_cmd_file()
+  filetype on
+
+  call writefile(['--rom_model'], 'Xfile.cmd')
+  split Xfile.cmd
+  call assert_equal('lnk', &filetype)
+  bwipe!
+
+  call writefile(['/* comment */'], 'Xfile.cmd')
+  split Xfile.cmd
+  call assert_equal('rexx', &filetype)
+  bwipe!
+
+  call writefile(['REM comment'], 'Xfile.cmd')
+  split Xfile.cmd
+  call assert_equal('dosbatch', &filetype)
+  bwipe!
+
+  filetype off
+endfunc
+
 func Test_sig_file()
   filetype on
 

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    982,
 /**/
     981,
 /**/