combine two small reads into one
combine two small reads into one

There's no need to read 1 byte and then immediately read 4 more, rather
than just reading 5 bytes to begin with. Also, with this change rxMsg is
no longer swallowing an error from ReadByte.

plopik/pgx,josephglanville/pgx,jonasi/pgx,jackc/pgx,kelvich/pgx,deoxxa/pgx,jackc/pgx,jackc/pgx,silviucm/pgx,silviucm/pgx,plopik/pgx,plopik/pgx,rsto/pgx,jackc/pgx,silviucm/pgx