[mythtv] Which target OSs in configure are actually used?

[Gary Buhrmaster]

On Mon, Nov 1, 2021 at 11:44 AM David Hampton via mythtv-dev
<mythtv-dev at mythtv.org> wrote:

> P.S. On my todo list (for after the next release) is to explore
> switching the builds to use cmake.

FWIW, At one point I toyed with Qt's "automated"
qmake .pro to cmake converter.  It did not work
well so well for this project, but it did provide
ideas.

One of the (useful) prereqs was some work to
identify where the project uses flags that
configure sets.  The one that I found fairly
quickly was the various big/little endian
fragments for which Qt has appropriate
abstractions and the code should be converted
to use.  I believe you have already done so for
a few cases, but there are others in the code.