libusb1: Update to 1.0.24

2020-12-09: v1.0.24
* Add new platform abstraction (#252)
* Add Null POSIX backend
* Add support for eventfd
* Add support for thread IDs on Haiku, NetBSD and Solaris
* New API libusb_hotplug_get_user_data()
* Darwin (macOS): Fix race condition that results in segmentation fault (#701)
* Darwin (macOS): Fix stale descriptor information post reset (#733)
* Darwin (macOS): use IOUSBDevice as darwin_device_class explicitly (#693)
* Linux: Drop support for kernel older than 2.6.32
* Linux: Provide an event thread name (#689)
* Linux: Wait until all USBs have been reaped before freeing them (#607)
* NetBSD: Recognize device timeouts (#710)
* OpenBSD: Allow opening ugen devices multiple times (#763)
* OpenBSD: Support libusb_get_port_number() (#764)
* SunOS: Fix a memory leak (#756)
* SunOS: Various fixes (#627, #628, #629)
* Windows: Add Visual Studio 2019 support
* Windows: Drop support for WinCE and Visual Studio older than 2013
* Windows: Drop support for Windows XP
* Windows: Support building all examples using Visual Studio (#151)
* Documentation fixes and improvements
* Various other bug fixes and improvements

(nia)