tizen: Can support linux as fallback TARGET_OS

tizen: Can support linux as fallback TARGET_OS

It can be helpful for platform developers
 to bypass tizen APIs on Tizen devices.

Might be useful for other RPM based distro,
 like Fedora for ARTIK, or (obsolete) Tizen profiles
 (with outdated Tizen packages).

Reformat options list to make nicer patches
 when configuration is changed (single word == single line).

Bug: https://jira.iotivity.org/browse/IOT-1320
Change-Id: Id1b37df55bbdebd7ada1413935f5306ccd1e0001
Origin: https://gerrit.iotivity.org/gerrit/#/c/12473/
Signed-off-by: Philippe Coval <philippe.coval@osg.samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/12473
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Dave Thaler <dthaler@microsoft.com>
Reviewed-by: Ziran Sun <ziran.sun@samsung.com>