nfp: bpf: remove the register renumbering leftovers

The register renumbering was removed and will not be coming back
in its old, naive form, given that it would be fundamentally
incompatible with calling functions.  Remove the leftovers.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>