remove BLT dependency from proxys

[Bubusch]

• remove BLT dependency from proxys to simplify build system

include( fe/SEMKernels/src/Shiva/tpl/camp/extern/blt/SetupBLT.cmake )
add_subdirectory( fe/SEMKernels )

• to be discussed with @rrsettgast -> can it be totally removed or moved down to SEMKernels ?
• also do we need camp ?

[rrsettgast]

Blt provides a lot of convenience. Can someone explain the reason to remove it?

[Bubusch]

I’m not familiar with BLT, but my goal is to keep the build system as lean as possible.
 Of course, if removing BLT means duplicating too much logic or losing useful features, I’m fine keeping it.
 Just trying to simplify where we can.

Also, if BLT is only used by Shiva in SEMKernels, it seems cleaner to move the include into SEMKernels itself.
 That way, proxys doesn’t need to be aware of BLT at all.
 Not sure it is feasible and what it implies though.

[Bubusch]

As discussed in weekly meeting, we will try to remove both blt and camp