wined3d: Put the SRG read capability check in its own function.

[wine] / dlls / quartz / quartz.spec

@ stdcall AMGetErrorTextA(long ptr long)
@ stdcall AMGetErrorTextW(long ptr long)
@ stdcall AmpFactorToDB(long)
@ stdcall DBToAmpFactor(long)
@ stdcall -private DllCanUnloadNow()
@ stdcall -private DllGetClassObject(ptr ptr ptr)
@ stdcall -private DllRegisterServer()
@ stdcall -private DllUnregisterServer()
@ stub GetProxyDllInfo