netdevsim: remove redundant branch

bool notify is referenced nowhere else in the function except to check
whether or not to call rtnl_offload_xstats_notify(). Remove it and move
the call to the previous branch.

Signed-off-by: Dennis Chen <dechen@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Link: https://patch.msgid.link/20250716165750.561175-1-dechen@redhat.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>