patch 9.0.0562: HSL playlist files are not recognized

Problem:    HSL playlist files are not recognized.
Solution:   Add a pattern to recognize HSL palylist files. (Benoît Ryder,
            closes #11204)

runtime/filetype.vim

@@ -844,6 +844,9 @@ au BufNewFile,BufRead *.hex,*.h32		setf hex
 " Hjson
 au BufNewFile,BufRead *.hjson			setf hjson
 
+" HLS Playlist
+au BufNewFile,BufRead *.m3u8			setf hlsplaylist
+
 " Hollywood
 au BufRead,BufNewFile *.hws			setf hollywood
 

src/testdir/test_filetype.vim

@@ -255,6 +255,7 @@ let s:filename_checks = {
     \ 'hex': ['file.hex', 'file.h32'],
     \ 'hgcommit': ['hg-editor-file.txt'],
     \ 'hjson': ['file.hjson'],
+    \ 'hlsplaylist': ['file.m3u8'],
     \ 'hog': ['file.hog', 'snort.conf', 'vision.conf'],
     \ 'hollywood': ['file.hws'],
     \ 'hoon': ['file.hoon'],

src/version.c

@@ -699,6 +699,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    562,
 /**/
     561,
 /**/