[zorg] [PowerPC] Limit number of threads to 64 on clang-ppc64le-rhel buildbot

This patch reduces the number of threads from 256 to 64 on the
clang-ppc64le-rhel buildbot.

Reviewed By: stefanp

Differential Revision: https://reviews.llvm.org/D88586
diff --git a/buildbot/osuosl/master/config/builders.py b/buildbot/osuosl/master/config/builders.py
index 0eca50d..0272a18 100644
--- a/buildbot/osuosl/master/config/builders.py
+++ b/buildbot/osuosl/master/config/builders.py
@@ -543,7 +543,7 @@
                                                                               "-DCMAKE_C_COMPILER_EXTERNAL_TOOLCHAIN:PATH=/opt/rh/devtoolset-7/root/usr",
                                                                               "-DCMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN:PATH=/opt/rh/devtoolset-7/root/usr",
                                                                               "-DLLVM_BINUTILS_INCDIR=/usr/include", "-DBUILD_SHARED_LIBS=ON", "-DLLVM_ENABLE_WERROR=ON",
-                                                                              '-DLLVM_LIT_ARGS="-vj 256"']),
+                                                                              "-DLLVM_LIT_ARGS='-vj 64'"]),
          'category' : 'clang'},
 
         {'name': "clang-s390x-linux",