Possibility to copy wgt without installing them

Adding a variable that control if wgt file should be automatically
installed. Now WGT are spread between autoinstall and manualinstall
directories.
By default autoinstall is chosen.

Change-Id: I51f4aa4426704714a77a53dab37adcaf5e1fd954
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/10105
Tested-by: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-build: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-boot-test: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
Reviewed-by: Stéphane Desneux <stephane.desneux@iot.bzh>