patch 8.2.2591: Poke files are not recognized

Problem:    Poke files are not recognized.
Solution:   Add a filetype entry. (Matt Ihlenfield)

src/testdir/test_filetype.vim

@@ -374,6 +374,7 @@ let s:filename_checks = {
     \ 'po': ['file.po', 'file.pot'],
     \ 'pod': ['file.pod'],
     \ 'pod6': ['file.pod6'],
+    \ 'poke': ['file.pk'],
     \ 'postscr': ['file.ps', 'file.pfa', 'file.afm', 'file.eps', 'file.epsf', 'file.epsi', 'file.ai'],
     \ 'pov': ['file.pov'],
     \ 'povini': ['.povrayrc'],

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2591,
 /**/
     2590,
 /**/