Superbuild - Explicitly set BUILD_COMMAND associated with CTK-Build step.
Superbuild - Explicitly set BUILD_COMMAND associated with CTK-Build step.

Setting CONFIGURE_COMMAND to an empty command is not enough to skip configuration step,
the BUILD_COMMAND should also be specified explicitly otherwise it will in-conditionally
default to 'make' on all platform.

See _ep_get_configure_command_id and _ep_get_build_command in ExternalProject.cmake

sankhesh/CTK,espakm/CTK,commontk/CTK,CJGoch/CTK,151706061/CTK,jcfr/CTK,151706061/CTK,naucoin/CTK,Sardge/CTK,SINTEFMedtek/CTK,msmolens/CTK,CJGoch/CTK,msmolens/CTK,danielknorr/CTK,commontk/CTK,Heather/CTK,jcfr/CTK,151706061/CTK,AndreasFetzer/CTK,lassoan/CTK,lassoan/CTK,151706061/CTK,pieper/CTK,vovythevov/CTK,vovythevov/CTK,SINTEFMedtek/CTK,ddao/CTK,sankhesh/CTK,Heather/CTK,commontk/CTK,msmolens/CTK,AndreasFetzer/CTK,CJGoch/CTK,espakm/CTK,finetjul/CTK,lassoan/CTK,danielknorr/CTK,Heather/CTK,SINTEFMedtek/CTK,rkhlebnikov/CTK,sankhesh/CTK,laurennlam/CTK,laurennlam/CTK,naucoin/CTK,fedorov/CTK,ddao/CTK,SINTEFMedtek/CTK,pieper/CTK,Sardge/CTK,fedorov/CTK,mehrtash/CTK,mehrtash/CTK,finetjul/CTK,laurennlam/CTK,msmolens/CTK,finetjul/CTK,SINTEFMedtek/CTK,espakm/CTK,CJGoch/CTK,151706061/CTK,jcfr/CTK,ddao/CTK,fedorov/CTK,Sardge/CTK,commontk/CTK,Heather/CTK,rkhlebnikov/CTK,AndreasFetzer/CTK,mehrtash/CTK,Sardge/CTK,vovythevov/CTK,danielknorr/CTK,danielknorr/CTK,naucoin/CTK,CJGoch/CTK,sankhesh/CTK,espakm/CTK,finetjul/CTK,pieper/CTK,laurennlam/CTK,AndreasFetzer/CTK,jcfr/CTK,lassoan/CTK,jcfr/CTK,naucoin/CTK,rkhlebnikov/CTK,rkhlebnikov/CTK,fedorov/CTK,vovythevov/CTK,mehrtash/CTK,pieper/CTK,ddao/CTK