session-rdp: Fix byte order for frames on big-endian machines
Quoting the commit message here:
gnome-remote-desktop currently assumes, that the byte order for frames
is always BGRX, regardless of the machine type. While for little endian
machines, this is true, but on big endian machines, the frame type is
XRGB. So, fix this accordingly.
Closes: https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/issues/191
The change itself was already tested as mentioned here: #191 (comment 2059029)