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 <philippe.coval@osg.samsung.com>

service/coap-http-proxy/SConscript

@@ -93,7 +93,7 @@ proxy_src = [
     './src/CoapHttpParser.c',
 ]
 
-if target_os in ['tizen']:
+if target_os in ['tizen', 'linux']:
     proxysdk = local_env.SharedLibrary('coap_http_proxy', proxy_src)
 else:
     proxysdk = local_env.StaticLibrary('coap_http_proxy', proxy_src)