config_tools: fix the issue that got wrong device name after specifying mac address

If user add the specific mac address (eg: mac=00:16:3E:77:A9:41)
in launch script, we will get the device name with the specified mac address.
This is unexpected. This patch updates the parser to fix the issue.

v1-->v2:
Update the parser with regex.

Tracked-On: projectacrn#7197
Signed-off-by: Kunhui-Li <[email protected]>
Reviewed-by: Junjie Mao <[email protected]>

Author: Kunhui-Li

misc/config_tools/launch_config/launch_script_template.sh

@@ -127,8 +127,10 @@ function add_virtual_device() {
 
     if [ "${kind}" = "virtio-net" ]; then
         # Create the tap device
-        tap_conf=${options%,*}
-        create_tap "${tap_conf#tap=}" >> /dev/stderr
+        if [[ ${options} =~ tap=([^,]+) ]]; then
+            tap_conf="${BASH_REMATCH[1]}"
+            create_tap "${tap_conf}" >> /dev/stderr
+        fi
     fi
 
     echo -n "-s ${slot},${kind}"