WIP: Direct service ctor calls at least on Android/iOS

Change-Id: I8a1907bc4b8f2134efb15d38a0fb5176b4384317
Don't enable OpenCL on OS X 10.5

Change-Id: I5b74d9a043c793ff5176b10786c09041207509a6
Reviewed-on: https://gerrit.libreoffice.org/7138
Reviewed-by: Norbert Thiebaud <nthiebaud@gmail.com>
Tested-by: Norbert Thiebaud <nthiebaud@gmail.com>