man_MANS install locations

[Jan Engelhardt]

Greetings.


A check was impleneted in rpmlint[1] that verifies that a manual page file such
as "foo.3" has indeed been placed in ${mandir}/man3, and not, say,
${mandir}/man4.
[1] 
https://github.com/rpm-software-management/rpmlint/commit/6fe4be934d60119f9a969a8b8198037e3f1c7941

Ironically, that check immediately triggered elsewhere in another
package in openSUSE distro, because some "foo.3pm" was located not in
${mandir}/man3pm but ${mandir}/man3. Upon a little research, I find
that e.g. on Solaris/Illumos, *.1m man pages are indeed in
/usr/share/man/man1m and not /usr/share/man/man1.

Given the following Makefile.am fragment, I find that automake 1.16.5
places manpages such (on Linux as well as Solaris):

$ cat Makefile.am
man_MANS = svcadm.1m
$ make install DESTDIR=$PWD/rt
make[1]: Entering directory '/tmp'
make[1]: Nothing to be done for 'install-exec-am'.
 /usr/bin/mkdir -p '/tmp/rt/usr/local/share/man/man1'
 /usr/bin/install -c -m 644 svcadm.1m '/tmp/rt/usr/local/share/man/man1'
make[1]: Leaving directory '/tmp'

Well, at least it is documented behavior:

```
   File extensions such as ‘.1c’ are handled by looking for the valid
part of the extension and using that to determine the correct
subdirectory of ‘mandir’.  Valid section names are the digits ‘0’
through ‘9’, and the letters ‘l’ and ‘n’.
```

When running automake on Solaris, placing svcadm.1m into man1 rather
than man1m seems outright wrong.
As for GNU/Linux, what was the rationale to only permit [0-9ln]?
Should automake be relaxed? Should the rpmlint check be adjusted
to cater to the GNU FHS?