mlxsw: core: Move functions to register/unregister array of traps to core.c

These functions belong to core.c alongside the functions that
register/unregister a single trap. Move it there. Make the functions
possibly usable by other parts of mlxsw code.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>