*: add "noexcept" to many, many function prototypes

This eliminates some overhead, because the compiler doesn't need to
consider these functions throwing.

src/output/plugins/PulseOutputPlugin.cxx

@@ -90,7 +90,6 @@ public:
 		Signal();
 	}
 
-	gcc_const
 	static bool TestDefaultDevice();
 
 	static PulseOutput *Create(const ConfigBlock &block);