darwin: fix 1 compiler warning

os/darwin_usb.c:248:18: warning: comparison of integers of different signs:
      'CFIndex' (aka 'long') and 'size_t' (aka 'unsigned long')
      [-Wsign-compare]
      if (length < size) {
          ~~~~~~ ^ ~~~~

Signed-off-by: Ludovic Rousseau <ludovic.rousseau@free.fr>
diff --git a/libusb/os/darwin_usb.c b/libusb/os/darwin_usb.c
index a19f04a..9284866 100644
--- a/libusb/os/darwin_usb.c
+++ b/libusb/os/darwin_usb.c
@@ -238,7 +238,7 @@
   return ret;
 }
 
-static int get_ioregistry_value_data (io_service_t service, CFStringRef property, size_t size, void *p) {
+static int get_ioregistry_value_data (io_service_t service, CFStringRef property, ssize_t size, void *p) {
   CFTypeRef cfData = IORegistryEntryCreateCFProperty (service, property, kCFAllocatorDefault, 0);
   int ret = 0;
 
diff --git a/libusb/version_nano.h b/libusb/version_nano.h
index 2847bad..4cd53ff 100644
--- a/libusb/version_nano.h
+++ b/libusb/version_nano.h
@@ -1 +1 @@
-#define LIBUSB_NANO 11083
+#define LIBUSB_NANO 11084