can: gs_usb: use common spelling of GS_USB in macros

There are a few macros in the driver which use GSUSB in the name of
the macro, while the majority uses GS_USB. Convert all macros to
GS_USB.

Fixes: d08e973a ("can: gs_usb: Added support for the GS_USB CAN devices")
Fixes: b00ca070

 ("can: gs_usb: activate quirks for CANtact Pro unconditionally")
Link: https://lore.kernel.org/all/20220827221548.3291393-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>