patch 9.1.1503: filetype: haxe files are not recognized

Problem:  filetype: haxe files are not recognized
Solution: detect *.hx files as haxe filetype (0xadk)

References:
- https://haxe.org/
- https://code.haxe.org/category/beginner/hello-world.html

closes: #17644

Signed-off-by: 0xadk <0xadk@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index 1236f08..f019c75 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -1100,6 +1100,9 @@
 au BufNewFile,BufRead *.ht			setf haste
 au BufNewFile,BufRead *.htpp			setf hastepreproc
 
+" Haxe
+au BufNewFile,BufRead *.hx			setf haxe
+
 " HCL
 au BufRead,BufNewFile *.hcl			setf hcl
 
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 7323d1e..2f5189d 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -348,6 +348,7 @@
     haskellpersistent: ['file.persistentmodels'],
     haste: ['file.ht'],
     hastepreproc: ['file.htpp'],
+    haxe: ['file.hx'],
     hb: ['file.hb'],
     hcl: ['file.hcl'],
     heex: ['file.heex'],
diff --git a/src/version.c b/src/version.c
index 5f51af9..9b2b53c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -720,6 +720,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1503,
+/**/
     1502,
 /**/
     1501,