patch 9.0.0583: only recognizing .m3u8 files is inconsistent

Problem:    Only recognizing .m3u8 files is inconsistent.
Solution:   Also matc .m3u files. (issue #11204)
diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index e537d93..06ffcfe 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -844,8 +844,8 @@
 " Hjson
 au BufNewFile,BufRead *.hjson			setf hjson
 
-" HLS Playlist
-au BufNewFile,BufRead *.m3u8			setf hlsplaylist
+" HLS Playlist (or another form of playlist)
+au BufNewFile,BufRead *.m3u,*.m3u8		setf hlsplaylist
 
 " Hollywood
 au BufRead,BufNewFile *.hws			setf hollywood
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index e2177e5..3b3d9a5 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -255,7 +255,7 @@
     \ 'hex': ['file.hex', 'file.h32'],
     \ 'hgcommit': ['hg-editor-file.txt'],
     \ 'hjson': ['file.hjson'],
-    \ 'hlsplaylist': ['file.m3u8'],
+    \ 'hlsplaylist': ['file.m3u', 'file.m3u8'],
     \ 'hog': ['file.hog', 'snort.conf', 'vision.conf'],
     \ 'hollywood': ['file.hws'],
     \ 'hoon': ['file.hoon'],
diff --git a/src/version.c b/src/version.c
index 79dda65..fdd6a23 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    583,
+/**/
     582,
 /**/
     581,