InstrumentTrack: set range of FX channel model to infinite when loadi…

…ng settings

When loading a project, instrument tracks usually are instantiated/loaded
before the FX mixer settings are loaded which results in an empty FX mixer
and thus 0 FX channels. The actual FX channel value for the instrument track
would be lost that way. Therefore set a big value which is being corrected
later by the FxMixerView for all instruments.

src/tracks/InstrumentTrack.cpp

@@ -803,6 +803,7 @@ void InstrumentTrack::loadTrackSpecificSettings( const QDomElement & _this )
 	}
 
 	m_pitchModel.loadSettings( _this, "pitch" );
+	m_effectChannelModel.setRange( 0, INT_MAX );
 	m_effectChannelModel.loadSettings( _this, "fxch" );
 
 	if( _this.hasAttribute( "baseoct" ) )