base-modem: plug leaks when organizing ports

The GLists maintained in the logic need to be explicitly freed (just
the lists, not the list contents) if we exit early on error or if we
end up deciding that the specific ports are available but unsupported
by the plugin (e.g. if a plugin that doesn't support net ports finds
net ports in the modem).

  ==225333== 24 bytes in 1 blocks are definitely lost in loss record 2,024 of 5,525
  ==225333==    at 0x483E77F: malloc (vg_replace_malloc.c:307)
  ==225333==    by 0x506C539: g_malloc (in /usr/lib/libglib-2.0.so.0.6600.7)
  ==225333==    by 0x508DC8F: g_slice_alloc (in /usr/lib/libglib-2.0.so.0.6600.7)
  ==225333==    by 0x50636B4: g_list_append (in /usr/lib/libglib-2.0.so.0.6600.7)
  ==225333==    by 0x17E671: mm_base_modem_organize_ports (mm-base-modem.c:1298)
  ==225333==    by 0x1E4409: mm_plugin_create_modem (mm-plugin.c:1094)
  ==225333==    by 0x162C81: mm_device_create_modem (mm-device.c:481)
  ==225333==    by 0x15DE60: device_support_check_ready (mm-base-manager.c:218)
  ==225333==    by 0x4EA8173: ??? (in /usr/lib/libgio-2.0.so.0.6600.7)
  ==225333==    by 0x4EAC6E8: ??? (in /usr/lib/libgio-2.0.so.0.6600.7)
  ==225333==    by 0x16730F: device_context_run_ready (mm-plugin-manager.c:1533)
  ==225333==    by 0x4EA8173: ??? (in /usr/lib/libgio-2.0.so.0.6600.7)

0 files changed, 0 insertions, 0 deletions