PhoshWayland: Ignore zwlr-output-management for the moment

Otherwise this leads to

(phosh:32074): phosh-wayland-DEBUG: 15:25:28.675: Output 38 removed
(phosh:32074): phosh-wayland-DEBUG: 15:25:28.676: key: 35, 0x62100018e650, 0x6070000744d0
(phosh:32074): phosh-monitor-manager-DEBUG: 15:25:28.676: Output 0 gone
(phosh:32074): phosh-wayland-DEBUG: 15:25:28.676: key: 35, 0x62100018e6e0, 0x6070000744d0
(phosh:32074): phosh-monitor-manager-DEBUG: 15:25:28.676: Output 1 gone
(phosh:32074): Gdk-DEBUG: 15:25:29.863: not a valid new object id (4278190081), message head(n)

when replugging an output.

    Librem5/phoc#13

We don't need the protocol right now.

Signed-off-by: Guido Günther <guido.gunther@puri.sm>
Status Job ID Name Coverage
  Build
passed #23101
librem5
build:native

00:02:22

 
  Test
passed #23102
librem5
test:native

00:01:23

passed #23103
librem5
test:smoke:one-output

00:02:16

passed #23104
librem5
test:smoke:two-outputs

00:02:15

 
  Package
passed #23105
librem5
package:deb

00:01:42