multi: fix a-vs-an typos

brontide/conn.go

@@ -104,7 +104,7 @@ func (c *Conn) ReadNextMessage() ([]byte, error) {
 }
 
 // Read reads data from the connection.  Read can be made to time out and
-// return a Error with Timeout() == true after a fixed time limit; see
+// return an Error with Timeout() == true after a fixed time limit; see
 // SetDeadline and SetReadDeadline.
 //
 // Part of the net.Conn interface.
@@ -129,7 +129,7 @@ func (c *Conn) Read(b []byte) (n int, err error) {
 }
 
 // Write writes data to the connection.  Write can be made to time out and
-// return a Error with Timeout() == true after a fixed time limit; see
+// return an Error with Timeout() == true after a fixed time limit; see
 // SetDeadline and SetWriteDeadline.
 //
 // Part of the net.Conn interface.

brontide/noise.go

@@ -464,7 +464,7 @@ func (b *Machine) GenActOne() ([ActOneSize]byte, error) {
 
 // RecvActOne processes the act one packet sent by the initiator. The responder
 // executes the mirrored actions to that of the initiator extending the
-// handshake digest and deriving a new shared secret based on a ECDH with the
+// handshake digest and deriving a new shared secret based on an ECDH with the
 // initiator's ephemeral key and responder's static key.
 func (b *Machine) RecvActOne(actOne [ActOneSize]byte) error {
 	var (