runtime(groff): Add compiler plugin for groff

Groff MOM (Macros for Manuscripts) is a macro package for the GNU
troff (groff) typesetting system, a light-weight alternative
to LaTeX for professional-quality documents.

closes: #15646

Signed-off-by: Konfekt <Konfekt@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/quickfix.txt b/runtime/doc/quickfix.txt
index e44c5d5..e7045c5 100644
--- a/runtime/doc/quickfix.txt
+++ b/runtime/doc/quickfix.txt
@@ -1,4 +1,4 @@
-*quickfix.txt*  For Vim version 9.1.  Last change: 2024 Aug 20
+*quickfix.txt*  For Vim version 9.1.  Last change: 2024 Sep 09
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1335,6 +1335,18 @@
 work, because Vim is then running in the same process as the compiler and
 stdin (standard input) will not be interactive.
 
+GROFF					*quickfix-groff* *compiler-groff*
+
+The GROFF compiler plugin uses the mom macro set (documented in the groff_mom
+manpage) as input and expects that the output file type extension is passed to
+make, say :make html or :make pdf.
+
+Additional arguments can be passed to groff by setting them in
+`b:groff_compiler_args` or `g:groff_compiler_args`. The `language` argument
+passed to groff is set using 'spelllang'; it can be overridden by setting
+`b:groff_compiler_lang`. The default enconding is `UTF-8` and can be changed
+by setting `b:groff_compiler_encoding` or `g:groff_compiler_encoding`.
+
 PANDOC					*quickfix-pandoc* *compiler-pandoc*
 
 The Pandoc compiler plugin expects that an output file type extension is
diff --git a/runtime/doc/tags b/runtime/doc/tags
index bd47526..77c02a8 100644
--- a/runtime/doc/tags
+++ b/runtime/doc/tags
@@ -6545,6 +6545,7 @@
 compiler-dotnet	quickfix.txt	/*compiler-dotnet*
 compiler-gcc	quickfix.txt	/*compiler-gcc*
 compiler-gnat	ft_ada.txt	/*compiler-gnat*
+compiler-groff	quickfix.txt	/*compiler-groff*
 compiler-hpada	ft_ada.txt	/*compiler-hpada*
 compiler-javac	quickfix.txt	/*compiler-javac*
 compiler-manx	quickfix.txt	/*compiler-manx*
@@ -9640,6 +9641,7 @@
 quickfix-error-lists	quickfix.txt	/*quickfix-error-lists*
 quickfix-functions	usr_41.txt	/*quickfix-functions*
 quickfix-gcc	quickfix.txt	/*quickfix-gcc*
+quickfix-groff	quickfix.txt	/*quickfix-groff*
 quickfix-index	quickfix.txt	/*quickfix-index*
 quickfix-manx	quickfix.txt	/*quickfix-manx*
 quickfix-pandoc	quickfix.txt	/*quickfix-pandoc*