twister: qemu: fix mps2_an521 on Windows

tfm_integration samples fail on Windows on mps2_an521 platform,
because output from ninja process running QEMU freezes in re-build
phase.
Fix it by implementing named pipes to read output from QEMU process
directly using os.open and os.read methods.

Signed-off-by: Michal Smola <michal.smola@nxp.com>