kbdif: Define "feature-raw-pointer" and "request-raw-pointer"

kbdif: Define "feature-raw-pointer" and "request-raw-pointer"

Backends set "feature-raw-pointer" if its capable of reporting
absolute positions without scaling the coordinates to screen
size. This should be set during the backend init.
Frontends set "request-raw-pointer" to request that backends
do not rescale absolute coordinates to screen size, and the
coordinates remain in the range [0, 0x7fff]. This request is
only applicable if "request-abs-pointer" is also set. Frontends
should set this value before setting Connected.

Signed-off-by: Owen Smith <owen.smith@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>