stdout is already unbuffered in bitbake code. Attempt to
do it again in devshell.bbclass causes this crash when
running devpyshell:
File "scripts/oepydevshell-internal.py", line 29, in <module>
pty = open(sys.argv[1], "w+b", 0)
IOError: [Errno 13] Permission denied: '/dev/pts/6'
Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
