Linux build support

src/audio/oal/channel.cpp

@@ -4,6 +4,10 @@
 #include "common.h"
 #include "sampman.h"
 
+#ifndef _WIN32
+#include <float.h>
+#endif
+
 extern bool IsFXSupported();
 
 CChannel::CChannel()
@@ -207,4 +211,4 @@ void CChannel::UpdateReverb(ALuint slot)
 	alSource3i(alSource, AL_AUXILIARY_SEND_FILTER, slot, 0, alFilter);
 }
 
-#endif
+#endif