Fixed tests for glib mutex and condition variable testing.

Fixed tests for glib mutex and condition variable testing.

Re-enabled tests that had previously been disabled due to taking too
long.

Removed sleep() calls from test code and replaced with combinations of
usleep() and volatile bools. Since condition variables are being tested
we did not want to use them in the validation process.

Retained debug printf statements, but added #define to turn them
off by default.

On one test system these changes moved the unit test from taking 24
seconds down to only 1.8 seconds.

Change-Id: I9b654a623f3aab9398b6f3aaa2366ab0fcdeb876
Signed-off-by: Jon A. Cruz <jonc@osg.samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/818
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Joseph Morrow <joseph.l.morrow@intel.com>
Reviewed-by: Charlie Lenahan <charlie.lenahan@intel.com>
Reviewed-by: Erich Keane <erich.keane@intel.com>