update godoc of RegisterInterchainAccount (cosmos#1256) (cosmos#1262)

## Description

The godoc of `RegisterInterchainAccount` was still saying that the port identifier was constructed using as well the connection identifiers. I corrected that.

closes: #XXXX

---

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- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
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(cherry picked from commit 4872c4b)

Co-authored-by: Carlos Rodriguez <carlos@interchain.io>
Co-authored-by: colin axnér <25233464+colin-axner@users.noreply.github.com>

modules/apps/27-interchain-accounts/controller/keeper/account.go

@@ -10,11 +10,10 @@ import (
 )
 
 // RegisterInterchainAccount is the entry point to registering an interchain account.
-// It generates a new port identifier using the owner address, connection identifier,
-// and counterparty connection identifier. It will bind to the port identifier and
-// call 04-channel 'ChanOpenInit'. An error is returned if the port identifier is
-// already in use. Gaining access to interchain accounts whose channels have closed
-// cannot be done with this function. A regular MsgChanOpenInit must be used.
+// It generates a new port identifier using the owner address. It will bind to the 
+// port identifier and call 04-channel 'ChanOpenInit'. An error is returned if the port
+// identifier is already in use. Gaining access to interchain accounts whose channels
+// have closed cannot be done with this function. A regular MsgChanOpenInit must be used.
 func (k Keeper) RegisterInterchainAccount(ctx sdk.Context, connectionID, owner string) error {
  portID, err := icatypes.NewControllerPortID(owner)
  if err != nil {