Fix up makefile .NOTPARALLEL heuristics so that linear building is only enforced if no object folder set and the "all" target is run. Rename library "ConfigDescriptor.c" file to "ConfigDescriptors.c" to ensure that object filenames are unique.

LUFA/Drivers/USB/Core/ConfigDescriptors.c

@@ -29,7 +29,7 @@
 */
 
 #define  __INCLUDE_FROM_USB_DRIVER
-#include "ConfigDescriptor.h"
+#include "ConfigDescriptors.h"
 
 #if defined(USB_CAN_BE_HOST)
 uint8_t USB_Host_GetDeviceConfigDescriptor(const uint8_t ConfigNumber,

LUFA/Drivers/USB/USB.h

@@ -41,7 +41,7 @@
  *
  *  \section Sec_Dependencies Module Source Dependencies
  *  The following files must be built with any user project that uses this module:
- *    - LUFA/Drivers/USB/Core/ConfigDescriptor.c <i>(Makefile source module name: LUFA_SRC_USB)</i>
+ *    - LUFA/Drivers/USB/Core/ConfigDescriptors.c <i>(Makefile source module name: LUFA_SRC_USB)</i>
  *    - LUFA/Drivers/USB/Core/DeviceStandardReq.c <i>(Makefile source module name: LUFA_SRC_USB)</i>
  *    - LUFA/Drivers/USB/Core/Events.c <i>(Makefile source module name: LUFA_SRC_USB)</i>
  *    - LUFA/Drivers/USB/Core/HostStandardReq.c <i>(Makefile source module name: LUFA_SRC_USB)</i>
@@ -382,7 +382,7 @@
 		#include "Core/USBTask.h"
 		#include "Core/Events.h"
 		#include "Core/StdDescriptors.h"
-		#include "Core/ConfigDescriptor.h"
+		#include "Core/ConfigDescriptors.h"
 		#include "Core/USBController.h"
 		#include "Core/USBInterrupt.h"