Forgot test case on previous commit

tests/qemuxml2argvdata/qemuxml2argv-channel-guestfwd.args

+LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test /usr/bin/qemu -S -M pc -m 214 -smp 1 -nographic -monitor unix:/tmp/test-monitor,server,nowait -no-acpi -boot c -hda /dev/HostVG/QEMUGuest1 -net none -serial none -parallel none -chardev pipe,id=channel0,path=/tmp/guestfwd -net user,guestfwd=tcp:10.0.2.1:4600-chardev:channel0 -usb

tests/qemuxml2argvdata/qemuxml2argv-channel-guestfwd.xml

+<domain type='qemu'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory>219200</memory>
+  <currentMemory>219200</currentMemory>
+  <vcpu cpuset='1-4,8-20,525'>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+    </disk>
+    <channel type='pipe'>
+      <source path='/tmp/guestfwd'/>
+      <target type='guestfwd' address='10.0.2.1' port='4600'/>
+    </channel>
+  </devices>
+</domain>