bpf: bpf_struct_ops: Remove unnecessary initial values of variables

err and tlinks is assigned first, so it does not need to initialize the
assignment.

Signed-off-by: Li kunyu <kunyu@nfschina.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230804175929.2867-1-kunyu@nfschina.com


Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>