Updating the debian/control file will automatically update the dependencies
in all CI environments that directly read the debian/control file, such
as Salsa-CI and buildbot.mariadb.org to some degree.
(https://github.com/MariaDB/mariadb.org-tools/issues/43)

On Debian/Ubuntu releases that don't have libpmem-dev available,
automatically omit it.

Debian/Ubuntu availability visible at:
- https://packages.debian.org/search?searchon=names&keywords=libpmem-dev
- https://packages.ubuntu.com/search?searchon=names&keywords=libpmem-dev

Also modify debian/rules to activate the use of PMEM, as it does not seem
to activate automatically.

The scope of this change is also Debian/Ubuntu only. No RPM or Windows or
Mac changes are included in this commit.

This commit does not update the external libmariadb or ColumnStore
CI pipelines, as those are maintained in different repositories.