Removed make & configure calls on Google Test library in every build.

Removed make & configure calls on Google Test library in every build.

By checking for the binary output directory of the Make script for
Google Test, the IoTivity SCons build will stop running the Configure
and Make scripts for every build on Linux.

Change-Id: Ib7ecb52c93fc0d2765ffd0e4112244660e732846
Signed-off-by: Joseph Morrow <joseph.l.morrow@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/817
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Erich Keane <erich.keane@intel.com>