Initial changes to remove xud dependancies when compiling with NO_USB=1

module_usb_audio/endpoint0/audiorequests.xc

@@ -2,7 +2,7 @@
  * @brief   Implements relevant requests from the USB Audio 2.0 Specification
  * @author  Ross Owen, XMOS Semiconductor
  */
-
+#ifndef NO_USB
 #include <xs1.h>
 #include "xud.h"
 #include "usb_std_requests.h"
@@ -1282,4 +1282,4 @@ XUD_Result_t AudioClassRequests_1(XUD_ep ep0_out, XUD_ep ep0_in, USB_SetupPacket
     return XUD_RES_ERR;
 }
 #endif
-
+#endif /* NO_USB */

module_usb_audio/endpoint0/endpoint0.c

@@ -7,6 +7,7 @@
 #include <safestring.h>
 #include <stddef.h>
 
+#ifndef NO_USB
 #include "xud.h"                 /* XUD user defines and functions */
 #include "usb_std_requests.h"
 #include "usbaudio20.h"          /* Defines from USB Audio 2.0 spec */
@@ -801,3 +802,4 @@ void Endpoint0(chanend c_ep0_out, chanend c_ep0_in, chanend c_audioControl,
         }
     }
 }
+#endif /* NO_USB */

module_usb_audio/endpoint0/vendorrequests.c

@@ -1,4 +1,4 @@
-
+#ifndef NO_USB
 
 #include "xud.h"
 #include "vendorrequests.h"
@@ -31,3 +31,4 @@ void VendorRequests_Init(VENDOR_REQUESTS_PARAMS_DEC)
 
 }
 
+#endif /* NO_USB */