qemuimage-testlib: Add delay to work around races in qemu startup

Qemu changes pid when starting up. On a loaded machine, this can result
in the incorrect pid being returned. Since qemu will take a few seconds to
boot anyway, we might as well delay a short while and allow things to settle
which should fix various race issues being seen on the autobuilder.

(From OE-Core rev: c0cecc16d4305b16ecfb4a51f6d5020d34909794)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

scripts/qemuimage-testlib

@@ -405,6 +405,8 @@ Test_Create_Qemu()
 		# Get the pid of the xterm processor, which will be used in Test_Kill_Qemu
 		XTERMPID=$!
 		echo "XTERMPID is $XTERMPID"
+		# When starting, qemu can reexecute itself and change PID so wait a short while for things to settle
+		sleep 5
 	fi
 
 	while [ ${up_time} -lt 10 ]