patch 8.2.3501: tmux filetype dection is incomplete

Problem:    tmux filetype dection is incomplete
Solution:   Also use tmux for files having text after .conf. (Eric Pruitt,
            closes #8971)

runtime/filetype.vim

@@ -2305,6 +2305,9 @@ au BufNewFile,BufRead .tcshrc*	call dist#ft#SetFileTypeShell("tcsh")
 " csh scripts ending in a star
 au BufNewFile,BufRead .login*,.cshrc*  call dist#ft#CSH()
 
+" tmux configuration with arbitrary extension
+au BufNewFile,BufRead {.,}tmux*.conf*		setf tmux
+
 " VHDL
 au BufNewFile,BufRead *.vhdl_[0-9]*		call s:StarSetf('vhdl')
 

src/testdir/test_filetype.vim

@@ -504,7 +504,7 @@ let s:filename_checks = {
     \ 'tidy': ['.tidyrc', 'tidyrc', 'tidy.conf'],
     \ 'tilde': ['file.t.html'],
     \ 'tli': ['file.tli'],
-    \ 'tmux': ['tmuxfile.conf', '.tmuxfile.conf', '.tmux-file.conf', '.tmux.conf', 'tmux-file.conf', 'tmux.conf'],
+    \ 'tmux': ['tmuxfile.conf', '.tmuxfile.conf', '.tmux-file.conf', '.tmux.conf', 'tmux-file.conf', 'tmux.conf', 'tmux.conf.local'],
     \ 'toml': ['file.toml'],
     \ 'tpp': ['file.tpp'],
     \ 'treetop': ['file.treetop'],

src/version.c

@@ -757,6 +757,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3501,
 /**/
     3500,
 /**/