P2P: Fix after_scan_tx processing during ongoing operations

P2P: Fix after_scan_tx processing during ongoing operations

When Action frame TX is postponed until a pending p2p_scan completes,
there may be additional operations that need to be continued after the
postponed Action frame TX operation completes. Fix this by starting
pending operation (if any) from TX status event for after_scan_tx
frames.

This fixes common errors seen with the test_discovery hwsim test case.

Signed-hostap: Jouni Malinen <j@w1.fi>