hidapi/mac: replace sprintf uses with snprintf.

Reference issues:
-  https://github.com/libusb/hidapi/pull/509
-  https://github.com/libusb/hidapi/pull/511

src/hidapi/mac/hid.c

@@ -854,7 +854,7 @@ hid_device * HID_API_EXPORT hid_open_path(const char *path, int bExclusive)
 				
 				/* Create the Run Loop Mode for this device.
 				 printing the reference seems to work. */
-				sprintf(str, "HIDAPI_%p", os_dev);
+				snprintf(str, sizeof(str), "HIDAPI_%p", os_dev);
 				dev->run_loop_mode = 
 				CFStringCreateWithCString(NULL, str, kCFStringEncodingASCII);