build_common: Removing redundant env configuration
Moving global environment configuration common for all
platforms into build_common/SConscript and removing repeated
lines from build_common/[platform]/SConscript.
Bug: https://jira.iotivity.org/browse/IOT-1583
Change-Id: Ic127e2c432ee50b0ba4aa91a460259d83d0b6b7d
Signed-off-by: Pawel Winogrodzki <pawelwi@microsoft.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/21287
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Dan Mihai <Daniel.Mihai@microsoft.com>