Scratchpad buffers allocation added to xHCI. Missing initialization steps
for keyboards - set configuration and set idle - added to USB. (Even
though they are specific to HID protocol, they go through USB command
endpoint, and with current module contents it's cleaner to have them
in USB module.)
Each `LOG_X` call declared a rather huge variable on the stack,
and using it to dump a whole structure often led to a page fault.
Now the temporary variables are `static`, which is a bit wasteful
on the kernel binary size, but easier to maintain.
Additionally bootloader updated to load kernels bigger than 64K.
`meson.build` rewritten with DRY principle. `deploy.sh` added,
which deploys the image on a installation USB stick borrowed from
another project. Image name aligned with the installer's expectations.
freywar