build-script-impl: Don't let distcc farm out cmake to run on other machines.

If cmake is run on another machine, the default Xcode path and
more in the cmake cache and ninja files will be of that machine's
configuration, not the local machine's.

Test with:
./utils/build-script -r -- --distcc --verbose

The cmake lines should start with ``/usr/local/bin/cmake`` instead of with
``/opt/distcc/pump``.

rdar://problem/29942258

Author: Doug Coleman

utils/build-script-impl

@@ -1544,7 +1544,7 @@ if [[ -n "${DISTCC}" ]]; then
     fi
 fi
 
-eval CMAKE_BUILD=("${DISTCC_PUMP}" "${CMAKE}" "--build")
+eval CMAKE_BUILD=("${CMAKE}" "--build")
 
 
 if [[ "${CMAKE_GENERATOR}" == "Xcode" ]]; then