package/freerdp: drop dependency on host-pkgconf

Currently, we only depend on host-pkgconf for gstreamer-0.x

However, we also need it at least for gstreamer-1.x and waylabnd, too.

But since FreeRDP is a cmake package, host-pkgconf is always pulled in
as a dependency by the cmake-package infrastructure.

So, drop the gstreamer-conditional host-pkgconf dependency.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Samuel Martin <s.martin49@gmail.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>