engine: Add const for some class methods

Author: dimhotepus

engine/audio/private/snd_channels.h

@@ -236,10 +236,10 @@ class CActiveChannels
 	void Add( channel_t *pChannel );
 	void Remove( channel_t *pChannel );
 
-	void GetActiveChannels( CChannelList &list );
+	void GetActiveChannels( CChannelList &list ) const;
 
 	void Init();
-	int	 GetActiveCount() { return m_count; }
+	int	 GetActiveCount() const { return m_count; }
 private:
 	int		m_count;
 	short	m_list[MAX_CHANNELS];

engine/audio/private/snd_dma.cpp

@@ -190,7 +190,7 @@ void CActiveChannels::Remove( channel_t *pChannel )
 }
 
 
-void CActiveChannels::GetActiveChannels( CChannelList &list )
+void CActiveChannels::GetActiveChannels( CChannelList &list ) const
 {
 	list.m_count = m_count;
 	if ( m_count )
@@ -387,7 +387,7 @@ const char *CSfxTable::getname()
 	return NULL;
 }
 
-FileNameHandle_t CSfxTable::GetFileNameHandle()
+FileNameHandle_t CSfxTable::GetFileNameHandle() const
 {
 	if ( s_Sounds.InvalidIndex() != m_namePoolIndex )
 	{

engine/audio/private/snd_sfx.h

@@ -24,7 +24,7 @@ class CSfxTable
 	virtual const char	*getname();
 	// gets the filename, the part after the optional prefixes
 	const char			*GetFileName();
-	FileNameHandle_t	GetFileNameHandle();
+	FileNameHandle_t	GetFileNameHandle() const;
 
 	void				SetNamePoolIndex( unsigned short index );
 	bool				IsPrecachedSound();