Octeontx2-af: Fix missing error code in cgx_probe()

When CGX fails mapping to NIX, set the error code to -ENODEV, currently
err is zero and that is treated as success path.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/aLAdlCg2_Yv7Y-3h@stanley.mountain/


Fixes: d280233f ("Octeontx2-af: Fix NIX X2P calibration failures")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251010204239.94237-1-harshit.m.mogalapalli@oracle.com


Signed-off-by: Paolo Abeni <pabeni@redhat.com>