This removes the earlier work done in libx52 to support USB hotplug.
This wasn't adequately tested, and the reason to have hotplug support
was to address perceived deficiencies in the standard API.
However, on recent reflection and experimentation, it seems to be easier
to support adding methods to connect to an X52/X52Pro joystick
dynamically after initializing the library. This approach also lends
itself to adding checks when sending control packets to close the device
handle when it detects device disconnection. Also, one could add a
disconnect method to disconnect from any connected joysticks.
Finally, this commit reverts a series of commits that chronicled my
journey into implementing hotplug support and simulating it in
libusbx52. By coalescing the revert into a single commit, it makes it
easier to revert the revert in the future, if necessary.
The stub libusb library used for testing writes the control request to a
dump file. By default, this file is block-buffered, and on a typical
Linux system, it waits until it receives about a page worth of data
before flushing it to disk. This results in a delay in monitoring
packets when running a debug program.
This change makes the file line-buffered instead, which results in the
debug output for every single packet getting flushed to disk without
having to wait for a full page of data.
With the release of libusb 1.0.22, `libusb_set_debug` has been
deprecated and replaced by `libusb_set_option`. This function is a new
generic API to add additional functionality in the future without having
to introduce new functions.
This change checks for `LIBUSB_API_VERSION` of at least `0x01000106`,
which is the version corresponding to 1.0.22, and if it matches, it
replaces the calls to `libusb_set_debug` with equivalent calls to
`libusb_set_option`.
nirenjan