can: sja1000: fix size of OCR_MODE_MASK define

[ Upstream commit 26e8f6a75248247982458e8237b98c9fb2ffcf9d ]

bitfield mode in ocr register has only 2 bits not 3, so correct
the OCR_MODE_MASK define.

Signed-off-by: Heiko Schocher <hs@denx.de>
Link: https://lore.kernel.org/all/20221123071636.2407823-1-hs@denx.de


Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>