Fix Gauss sound not stopping when players are not in the PAS

[SamVanheer]

The Gauss gun's charging sound is not stopped when players who were in the Potentially Audible Set (PAS) when it started are not in PAS when the sound is stopped:

halflife/dlls/gauss.cpp

Line 392 in c7240b9

PLAYBACK_EVENT_FULL( FEV_NOTHOST | FEV_RELIABLE, m_pPlayer->edict(), m_usGaussFire, 0.01, (float *)&m_pPlayer->pev->origin, (float *)&m_pPlayer->pev->angles, 0.0, 0.0, 0, 0, 0, 1 );

This is because the event is missing the FEV_GLOBAL flag.

To fix this the flag should be added:

PLAYBACK_EVENT_FULL( FEV_NOTHOST | FEV_RELIABLE | FEV_GLOBAL, m_pPlayer->edict(), m_usGaussFire, 0.01, (float *)&m_pPlayer->pev->origin, (float *)&m_pPlayer->pev->angles, 0.0, 0.0, 0, 0, 0, 1 );

This is not the same issue as #3188, which concerns missing event playback when the weapon is in certain states.