- new API function: `struct hid_device_info * hid_get_device_info(hid_device *dev);` to get `hid_device_info` after the device already opened;
- reused existing implementation on Windows and macOS from enumeration routines to have the implementation;
- refactored libusb implementation to have a shared routine for `hid_enumerate` and `hid_get_device_info`;
- refactored hidraw implementation to have a shared routine for `hid_enumerate` and `hid_get_device_info`;

Resolves: signal11#431
Closes: signal11#164
Closes: signal11#163

…(#497)

Commit 5c9f147 (signal11#432) replaced a call to strdup with an explicit
memcpy to a buffer on the stack.

However, it incorrectly used the buffer size, instead of the clamped
uevent length, as the argument to memcpy, resulting in reads past the
end of uevent:

Fix this by using uevent_len as the argument to memcpy.

Calling strndupa was considered but abandoned, as it is not standard.

Fixes: 5c9f147 (signal11#432)
Fixes: 4779d63d8760