can: mcp251xfd: mcp251xfd_chip_start(): fix error handling for mcp251xfd_chip_rx_int_enable()

This patch fixes the error handling for mcp251xfd_chip_rx_int_enable().
Instead just returning the error, properly shut down the chip.

Link: https://lore.kernel.org/all/20211106201526.44292-2-mkl@pengutronix.de


Fixes: 55e5b97f ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>