vim-patch:9.2.0788: filetype: hip files are not recognized (#40809)

Problem:  filetype: hip files are not recognized
Solution: Detect *.hip files as hip filetype, include filetype, syntax
          and indent plugins, update makemenu.vim and synmenu.vim (Young)

Round out HIP (Heterogeneous-compute Interface for Portability) support
to mirror the existing CUDA files:

- autoload/dist/ft.vim: detect the ".hip" extension as filetype "hip"
- ftplugin/hip.vim: behave like C++ by sourcing ftplugin/cpp.vim
- indent/hip.vim: use cindent, like indent/cuda.vim
- makemenu.vim / synmenu.vim: add a Syntax menu entry

The syntax/hip.vim file already sources syntax/cpp.vim and adds the
HIP-specific keywords, matching syntax/cuda.vim.

closes: vim/vim#20773

b3ad239038

Co-authored-by: Young <young20050727@gmail.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

runtime/lua/vim/filetype.lua

@@ -638,6 +638,7 @@ local extension = {
   ihe = 'hex',
   ihx = 'hex',
   mcs = 'hex',
+  hip = 'hip',
   hjson = 'hjson',
   m3u = 'hlsplaylist',
   m3u8 = 'hlsplaylist',