patch 9.1.0906: filetype: Nvidia PTX files are not recognized

Problem:  filetype: Nvidia PTX files are not recognized
Solution: detect '*.ptx' files as ptx filetype (Yinzuo Jiang)

Reference: https://docs.nvidia.com/cuda/parallel-thread-execution/

closes: #16171

Signed-off-by: Yinzuo Jiang <jiangyinzuo@foxmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_filetype.vim

@@ -608,6 +608,7 @@ def s:GetFilenameChecks(): dict<list<string>>
     ps1xml: ['file.ps1xml'],
     psf: ['file.psf'],
     psl: ['file.psl'],
+    ptx: ['file.ptx'],
     pug: ['file.pug'],
     puppet: ['file.pp'],
     purescript: ['file.purs'],

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    906,
 /**/
     905,
 /**/