Input: navpoint - remove driver

This driver does not use the SPI core as it should, instead tampering
with the SSP registers manually. Refactoring the driver is almost
certainly not worth it as the hardware seems to have been designed for
and used only in the HP iPAQ hx4700 removed more than a year ago in
d6df7df7

 ("ARM: pxa: remove unused board files"), so let's remove
it.

Signed-off-by: Duje Mihanović <duje.mihanovic@skole.hr>
Link: https://lore.kernel.org/r/20240116-navpoint-removal-v2-2-e566806f1009@skole.hr
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>