patch 9.1.0610: filetype: OpenGL Shading Language files are not detected

Problem:  filetype: OpenGL Shading Language files are not detected
Solution: detect various file extensions as GLSL filetype, include
          indent and syntax script, do no longer recognize '*.comp'
          as Mason filetype (Gregory Anders)

closes: #15317

Signed-off-by: Gregory Anders <greg@gpanders.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/indent/glsl.vim

@@ -0,0 +1,14 @@
+" Language: OpenGL Shading Language
+" Maintainer: Gregory Anders <greg@gpanders.com>
+" Last Modified: 2024 Jul 21
+" Upstream: https://github.com/tikhomirov/vim-glsl
+
+if exists('b:did_indent')
+  finish
+endif
+let b:did_indent = 1
+
+setlocal autoindent cindent
+setlocal cinoptions&
+
+let b:undo_indent = 'setl ai< ci< cino<'