package/ola: fix build against google.protobuf

To test for the google.protobuf presence, ola's ./conifgure runs the
host Python. This is doomed to fail, as google.protobuf is installed
in target/ and not in host/

Since our dependencies ensures that google.protobuf is indeed installed
before we attempt to configure and build ola, we can just ditch the
test altogether.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>