coap-http-proxy: Build shared lib also on linux
coap-http-proxy: Build shared lib also on linux

Bug: https://jira.iotivity.org/browse/IOT-1745
Change-Id: Ie7196851c3e623f383e6727b5cbd1c29cf1ae6ac
Signed-off-by: Philippe Coval <ff46fec9739d31cce915aabcc3a7a2c00eee4d6c@osg.samsung.com>

rzr/iotivity,rzr/iotivity,iotivity/iotivity,iotivity/iotivity,iotivity/iotivity,iotivity/iotivity,iotivity/iotivity,iotivity/iotivity,rzr/iotivity,rzr/iotivity,iotivity/iotivity,rzr/iotivity,rzr/iotivity,rzr/iotivity,iotivity/iotivity