build: limit to 2.36 GLib API

Fixes the following build warning:
  make[4]: Entering directory '/home/aleksander/libmbim/src/libmbim-glib'
    CC       libmbim_glib_core_la-mbim-device.lo
  mbim-device.c: In function ‘mbim_device_init’:
  mbim-device.c:2405:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
   2405 |     self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, MBIM_TYPE_DEVICE, MbimDevicePrivate);
1 file changed