vim-patch:9.1.0876: filetype: openCL files are not recognized

Problem:  filetype: openCL files are not recognized
Solution: detect '*.cl' files as opencl or lisp filetype,
          include a opencl syntax and filetype plugin (Wu, Zhenyu)

closes: vim/vim#15825

e2c27ca8ef

Co-authored-by: Wu, Zhenyu <wuzhenyu@ustc.edu>

runtime/lua/vim/filetype.lua

@@ -300,6 +300,7 @@ local extension = {
   cho = 'chordpro',
   chordpro = 'chordpro',
   ck = 'chuck',
+  cl = detect.cl,
   eni = 'cl',
   icl = 'clean',
   cljx = 'clojure',
@@ -688,7 +689,6 @@ local extension = {
   ily = 'lilypond',
   liquid = 'liquid',
   liq = 'liquidsoap',
-  cl = 'lisp',
   L = 'lisp',
   lisp = 'lisp',
   el = 'lisp',

runtime/lua/vim/filetype/detect.lua

@@ -180,6 +180,16 @@ function M.changelog(_, bufnr)
   return 'changelog'
 end
 
+--- @type vim.filetype.mapfn
+function M.cl(_, bufnr)
+  local lines = table.concat(getlines(bufnr, 1, 4))
+  if lines:match('/%*') then
+    return 'opencl'
+  else
+    return 'lisp'
+  end
+end
+
 --- @type vim.filetype.mapfn
 function M.class(_, bufnr)
   -- Check if not a Java class (starts with '\xca\xfe\xba\xbe')