remove unnecessary lock when process data from stream. Reading data from stream is single thread processing, no need to lock connection => readLoop => parser.parse => processMsg
remove unnecessary lock when process data from stream.
Reading data from stream is single thread processing, no need to lock
connection => readLoop => parser.parse => processMsg

Signed-off-by: Tamnm <ed883b8051b2aa8faaffba4e8d51e79008058fb9@goquo.com>

nats-io/csnats,stephenjannin/csnats