nfp: bpf: don't do ld/shifts combination if shifts are jump destination

If any of the shift insns in the ld/shift sequence is jump destination,
don't do combination.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>