Hi Alex,
Thanks for responding.
 
I have tried below steps:
1. Adding meta-xfce and meta-gnome layers to bblayers.conf.
2.  IMAGE_INSTALL:append = " packagegroup-core-x11-xserver packagegroup-core-x11-utils packagegroup-core-x11 packagegroup-xfce-extended packagegroup-xfce-base mesa" to core-image-base.bb
3. IMAGE_INSTALL:append = "  xterm xclock xprop dbus dbus-x11 pointercal twm mini-x-session liberation-fonts" to local.conf.
 
After boot, 
1. Installed xprg package &run startx  command 
2. Error: PFA
 
Is there anything that I am missing here?
 
Thanks