leaudio: Fix handling invalid offloader behaviour

This fix handles scenario when offloader calles Resume while it was
already called.

BT stack in such case cleares audio_sender_state and
audio_receiver_state and should not continue with setting up stream when
state machine gets there.

Bug: 297846817
Test: atest bluetooth_le_audio_test
Tag: #feature
Change-Id: If113e23c9383e10c59fc4c409e3d3a12b2e35804