fix "multiple mods in the same attack weren't themed correctly"

stepmania/src/ActiveAttackList.cpp

@@ -44,6 +44,8 @@ void ActiveAttackList::Update( float fDelta )
 			for( unsigned j=0; j<asMods.size(); j++ )
 			{
 				CString& sMod = asMods[j];
+				TrimLeft( sMod );
+				TrimRight( sMod );
 
 				sMod = PlayerOptions::ThemeMod( sMod );