qemuimage-testlib: Ensure TOPDIR/BUILDDIR are set

The recent environment changes mean TOPDIR/BUILDDIR need to be exported
specifcially to the enviromnent so the qemu scripts can find the correct
build directory.

Without this, qemu can fail to run.

Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

meta/classes/imagetest-qemu.bbclass

@@ -55,6 +55,7 @@ def qemuimagetest_main(d):
         os.environ["QEMUTARGET"] = pname
         os.environ["DISPLAY"] = bb.data.getVar("DISPLAY", d, True)
         os.environ["POKYBASE"] = bb.data.getVar("POKYBASE", d, True)
+        os.environ["TOPDIR"] = bb.data.getVar("TOPDIR", d, True)
 
         """run Test Case"""
         bb.note("Run %s test in scenario %s" % (case, scen))

scripts/qemuimage-testlib

@@ -396,7 +396,8 @@ Test_Create_Qemu()
 	export MACHINE=$QEMUARCH
 
 	# Create Qemu in localhost VNC Port 1
-    	xterm -display ${DISPLAY} -e "${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE}" &
+	echo "Running xterm -display ${DISPLAY} -e 'BUILDDIR=${TOPDIR} ${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE}' &"
+    	xterm -display ${DISPLAY} -e "BUILDDIR=${TOPDIR} ${RUNQEMU} ${KERNEL} ${TEST_ROOTFS_IMAGE}" &
 
 	# Get the pid of the xterm processor, which will be used in Test_Kill_Qemu
 	PID=$!