(get_configuration_state, restore_configuration_state): New functions.
(get_configuration_state, restore_configuration_state): New functions.

(selftest): Save and restore configuration test around the test.
Notably, this will normally deactivate loopback mode again.

Igalia/snabb,eugeneia/snabb,dpino/snabbswitch,Igalia/snabb,wingo/snabb,wingo/snabbswitch,andywingo/snabbswitch,snabbnfv-goodies/snabbswitch,hb9cwp/snabbswitch,kbara/snabb,wingo/snabbswitch,snabbco/snabb,eugeneia/snabbswitch,alexandergall/snabbswitch,dwdm/snabbswitch,lukego/snabb,Igalia/snabb,xdel/snabbswitch,hb9cwp/snabbswitch,dpino/snabb,Igalia/snabb,lukego/snabb,lukego/snabbswitch,mixflowtech/logsensor,mixflowtech/logsensor,fhanik/snabbswitch,aperezdc/snabbswitch,virtualopensystems/snabbswitch,alexandergall/snabbswitch,eugeneia/snabb,snabbco/snabb,wingo/snabb,snabbnfv-goodies/snabbswitch,javierguerragiraldez/snabbswitch,eugeneia/snabb,dpino/snabbswitch,dpino/snabb,snabbco/snabb,alexandergall/snabbswitch,pirate/snabbswitch,Igalia/snabb,hb9cwp/snabbswitch,dwdm/snabbswitch,SnabbCo/snabbswitch,plajjan/snabbswitch,SnabbCo/snabbswitch,fhanik/snabbswitch,javierguerragiraldez/snabbswitch,eugeneia/snabb,snabbco/snabb,dwdm/snabbswitch,alexandergall/snabbswitch,alexandergall/snabbswitch,alexandergall/snabbswitch,snabbco/snabb,heryii/snabb,pavel-odintsov/snabbswitch,alexandergall/snabbswitch,Igalia/snabb,kbara/snabb,snabbnfv-goodies/snabbswitch,eugeneia/snabb,hb9cwp/snabbswitch,mixflowtech/logsensor,lukego/snabbswitch,heryii/snabb,javierguerragiraldez/snabbswitch,fhanik/snabbswitch,heryii/snabb,mixflowtech/logsensor,kbara/snabb,wingo/snabbswitch,alexandergall/snabbswitch,kbara/snabb,eugeneia/snabbswitch,pirate/snabbswitch,Igalia/snabbswitch,dpino/snabb,eugeneia/snabb,snabbco/snabb,heryii/snabb,justincormack/snabbswitch,wingo/snabb,Igalia/snabb,plajjan/snabbswitch,heryii/snabb,justincormack/snabbswitch,justincormack/snabbswitch,pavel-odintsov/snabbswitch,Igalia/snabbswitch,aperezdc/snabbswitch,kellabyte/snabbswitch,eugeneia/snabbswitch,plajjan/snabbswitch,snabbnfv-goodies/snabbswitch,dpino/snabb,andywingo/snabbswitch,wingo/snabb,kellabyte/snabbswitch,eugeneia/snabb,snabbco/snabb,dpino/snabbswitch,andywingo/snabbswitch,justincormack/snabbswitch,plajjan/snabbswitch,Igalia/snabbswitch,aperezdc/snabbswitch,kbara/snabb,Igalia/snabbswitch,virtualopensystems/snabbswitch,pavel-odintsov/snabbswitch,andywingo/snabbswitch,pirate/snabbswitch,dpino/snabb,SnabbCo/snabbswitch,dpino/snabb,mixflowtech/logsensor,Igalia/snabbswitch,xdel/snabbswitch,dpino/snabb,heryii/snabb,wingo/snabb,eugeneia/snabb,lukego/snabb,wingo/snabbswitch,aperezdc/snabbswitch,SnabbCo/snabbswitch,xdel/snabbswitch,lukego/snabb,kbara/snabb,lukego/snabbswitch,snabbco/snabb,dpino/snabbswitch,kellabyte/snabbswitch,lukego/snabbswitch,virtualopensystems/snabbswitch,eugeneia/snabbswitch,Igalia/snabb,wingo/snabb