HID: rmi: fix masks for x and w_x data

The F11 data in the HID report contains four bits of data for w_x and the least significant bits
of x. Currently only the first three bits are being used which is resulting in small jumps in
the position data on the x axis and in the w_x data.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>