Convert the USES table into multiple <sect1>.

To translators, the only text change are:

• The chapter title;
• For each argument entry, the text "Possible arguments: " is prepended to the argument list;
• The first sect1 is new;

The rest of the change is, replace <row> tags with <sect1>, replace the
first <entry> of each <row> by a <title>, and the following <entry> by
<para>.

Approved by: wblock (mentor)
MFH:
Relnotes:
Sponsored by: Absolight
Differential Revision: https://reviews.freebsd.org/D3142