audio_device: Fix unused variable warning

In some configurations local variable p_desc_parse_for_params
is declared and never used resulting in warning that can
be escalated to build error (for mynewt)

Now variable is surrounded with same preprocessor condition
as function that uses it audiod_parse_for_AS_params()

Author: kasjer

src/class/audio/audio_device.c

@@ -1729,7 +1729,7 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const *
     // Find correct interface
     if (tu_desc_type(p_desc) == TUSB_DESC_INTERFACE && ((tusb_desc_interface_t const * )p_desc)->bInterfaceNumber == itf && ((tusb_desc_interface_t const * )p_desc)->bAlternateSetting == alt)
     {
-#if CFG_TUD_AUDIO_ENABLE_ENCODING || CFG_TUD_AUDIO_ENABLE_DECODING || CFG_TUD_AUDIO_EP_IN_FLOW_CONTROL
+#if (CFG_TUD_AUDIO_ENABLE_EP_IN && (CFG_TUD_AUDIO_EP_IN_FLOW_CONTROL || CFG_TUD_AUDIO_ENABLE_ENCODING)) || (CFG_TUD_AUDIO_ENABLE_EP_OUT && CFG_TUD_AUDIO_ENABLE_DECODING)
       uint8_t const * p_desc_parse_for_params = p_desc;
 #endif
       // From this point forward follow the EP descriptors associated to the current alternate setting interface - Open EPs if necessary