cobol: Fix up update_web_docs_git for COBOL [PR119227]

cobol: Fix up update_web_docs_git for COBOL [PR119227]

As mentioned in the PR, the COBOL documentation is currently not present
in onlinedocs at all.
While the script generates gcobol{,-io}.{pdf,html}, it generates them in
the gcc/gcc/cobol/ subdirectory of the update_web_docs_git temporary
directory and nothing find it there afterwards, all the processing is on
for file in */*.html *.ps *.pdf *.tar; do
So, this patch puts gcobol{,-io}.html into gcobol/ subdirectory and
gcobol{,-io}.pdf into the current directory, so that it is picked up.
With this it makes into onlinedocs:
find . -name \*cobol\*
./onlinedocs/gcobol.pdf.gz
./onlinedocs/gcobol.pdf
./onlinedocs/gcobol_io.pdf.gz
./onlinedocs/gcobol_io.pdf
./onlinedocs/gcobol
./onlinedocs/gcobol/gcobol_io.html.gz
./onlinedocs/gcobol/gcobol_io.html
./onlinedocs/gcobol/gcobol.html.gz
./onlinedocs/gcobol/gcobol.html
./onlinedocs/gnat_rm/gnat_005frm_002finterfacing_005fto_005fother_005flanguages-interfacing-to-cobol.html.gz
./onlinedocs/gnat_rm/gnat_005frm_002finterfacing_005fto_005fother_005flanguages-interfacing-to-cobol.html
./onlinedocs/gnat_rm/gnat_005frm_002fimplementation_005fadvice-rm-f-7-cobol-support.html.gz
./onlinedocs/gnat_rm/gnat_005frm_002fimplementation_005fadvice-rm-f-7-cobol-support.html
./onlinedocs/gnat_rm/gnat_005frm_002fimplementation_005fadvice-rm-b-4-95-98-interfacing-with-cobol.html.gz
./onlinedocs/gnat_rm/gnat_005frm_002fimplementation_005fadvice-rm-b-4-95-98-interfacing-with-cobol.html

2025-04-07  Jakub Jelinek  <jakub@redhat.com>

	PR web/119227
	* update_web_docs_git: Rename mdoc2pdf_html to cobol_mdoc2pdf_html,
	perform mkdir -p $DOCSDIR/gcobol gcobol, remove $d/ from pdf and in
	html replace it with gcobol/; update uses of the renamed function.