Kenny Levinsen authored Nov 22, 2020 and Pekka Paalanen committed Apr 14, 2021

get_vt is used to check if VTs are enabled, by verifying that a VT greater than
0 is returned.

libseat always implements switching, with switch to an active session
currently being a noop in all backends. libseat does not currently have
a get_vt implementation. Make get_vt errors more explicit, and allow VT
switching anyway if the error is ENOSYS.

Signed-off-by: Kenny Levinsen <kl@kl.wtf>