Anti-'Mech infantry "swarm" attacks are assumed to include satchel charges and the like. (In fact, pg220 TW opens the infantry section's "Anti-'Mech Attacks" with the statement, "Most infantry units can make specialized anti-'Mech attacks, which involve closing with a 'Mech, climbing it and planting satchel charges in strategic, vulnerable locations.")
pg220 TW also notes (under "Swarm Attacks") that vehicles may be subject to swarm attacks, too.
TacOps pg341 addresses infantry with the SCUBA specialization.
So, yes, the game already allows infantry to swarm naval vessels and plant limpet charges. You don't need to specially equip infantry with the limpet/satchel charges; infantry with anti-'Mech training are assumed to have them and it's worked into their basic swarm damage.