Delete pbuilder since it is not needed anymore.
Change-Id: I685547e9692944b89521864fc3bee4e9a2f1139f
Signed-off-by: Antonello Dettori <dev@dettori.io>
Reviewed-on: https://review.coreboot.org/15955
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Omar Pakker
Reviewed-by: Patrick Georgi <pgeorgi@google.com>