Disable shared pixmaps on MIT-SHM

Our internal pixmap representation does not match what we advertice in
out pixmap formats, and there is no way to only enable 24 and 32 depth
pixmaps for SHM so just disable them all together. MIT-SHM can still be
used through Shm{Get,Put}Image. We probably should store pixmaps as we
say we do, but its too much work for now :^)

xbanan/Base.cpp

@@ -2052,8 +2052,7 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 						.depth = request.depth,
 						.width = request.width,
 						.height = request.height,
-						.data = data.span(),
-						.owned_data = BAN::move(data),
+						.data = BAN::move(data),
 					}
 				}))
 			));