Fix generation of distribution tarball

Fix generation of distribution tarball

This issue can be reproduced by running `make dist` from the root of the
tree.  Error introduced in fcb21b3, where additions of links in
installation.sgml require custom rules in standalone-profile.xsl to make
sure that ./INSTALL is generated correctly for the distribution tarball,
where links are replaced by equivalent terms from the profile file
changed by this commit.

Per buildfarm member guaibasaurus.

Discussion: https://postgr.es/m/ZD859FmcMRCNtz0W@paquier.xyz