RootCanal H4: Add recovery state

The recovery state is entered when an invalid Idc
is received. In recovery state, all bytes are dropped
until a valid HCI Reset command is received.
The reasoning is that this issue occurs when the emulator
is rebooted, leaving bytes in the VirtIO console.
The next valid command should be HCI Reset command then.

Test: atest rootcanal_test_host
Bug: 261261502
Change-Id: I6e5482d9b2642fa789e6ed415ce3833663097bff