Need to disable Libmv for cudakernels target

This way no access to automated tests variables will happen.

Ideally it should be something more like using blenderlite
with just Cycles enabled, but let's keep it for a bigger
clean up.

SConstruct

@@ -272,6 +272,7 @@ if 'cudakernels' in B.targets:
     env['WITH_BF_CYCLES'] = True
     env['WITH_BF_CYCLES_CUDA_BINARIES'] = True
     env['WITH_BF_PYTHON'] = False
+    env['WITH_BF_LIBMV'] = False
 
 # Configure paths for automated configuration test programs
 env['CONFIGUREDIR'] = os.path.abspath(os.path.normpath(os.path.join(env['BF_BUILDDIR'], "sconf_temp")))