can: mcp251xfd: mcp251xfd_register_get_dev_id(): fix return of error value

stable inclusion
from stable-v5.10.110
commit 3b9fabe8f6e80b884e830d3cf715be81534e8845
bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3b9fabe8f6e80b884e830d3cf715be81534e8845

--------------------------------

commit fa7b514d upstream.

Clang static analysis reports this issue:

| mcp251xfd-core.c:1813:7: warning: The left operand
|   of '&' is a garbage value
|   FIELD_GET(MCP251XFD_REG_DEVID_ID_MASK, dev_id),
|   ^                                      ~~~~~~

dev_id is set in a successful call to mcp251xfd_register_get_dev_id().
Though the status of calls made by mcp251xfd_register_get_dev_id() are
checked and handled, their status' are not returned. So return err.

Fixes: 55e5b97f ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Link: https://lore.kernel.org/all/20220319153128.2164120-1-trix@redhat.com


Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>