[mythtv-users] Documentation needs update in section 20.9

[Daborg]

The documentation in section 20.9 (Removing unwanted channels) needs to
be updated.

The subsection explaining how to remove the channels from the database
is incorrect and can cause one to lose channels they want.

The CURRENT wording is:
$ mysql -u root mythconverg
mysql> delete from channel where chanid = '1015';


The proper way to remove the channels is:
$ mysql -u root mythconverg
mysql> delete from channel where channum = '15';

For instance in my setup the SciFi channel is 61.  But in the table it is channid 78.  This has to do with the fact that some channels for some reason actually have multiple names.  example channel 15 is LOORIG15, GOVT15.  Thus using channum instead of channid provides the expected results.

Scott