bitbake: toaster: set BITBAKE_UI environment variable

Set BITBAKE_UI variable to 'toastergui' for command line builds
to use toasterui as a default ui module for bitbake.

(Bitbake rev: 9ad6393d30cb6196cf7c9a5adcf33febd724d294)

Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: Michael Wood <michael.g.wood@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/bin/toaster

@@ -100,6 +100,7 @@ stop_system()
     unset DATABASE_URL
     unset TOASTER_CONF
     unset TOASTER_DIR
+    unset BITBAKE_UI
     trap - SIGHUP
     #trap - SIGCHLD
     INSTOPSYSTEM=0
@@ -259,6 +260,7 @@ case $CMD in
             echo "Failed ${CMD}."
             return 4
         fi
+        export BITBAKE_UI='toasterui'
         export DATABASE_URL=`$MANAGE get-dburl`
         $MANAGE runbuilds & echo $! >${BUILDDIR}/.runbuilds.pid
         # set fail safe stop system on terminal exit