clang-x86-ninja-win10: removed quotes around LIT_TOOLS_DIR

Hopefully this will fix the failing build:
http://lab.llvm.org:8014/#/builders/27/builds/1089
diff --git a/buildbot/osuosl/master/config/builders.py b/buildbot/osuosl/master/config/builders.py
index db745f2..0107b71 100644
--- a/buildbot/osuosl/master/config/builders.py
+++ b/buildbot/osuosl/master/config/builders.py
@@ -1803,7 +1803,7 @@
                                         '-DCMAKE_C_COMPILER_LAUNCHER=sccache',
                                         '-DCMAKE_CXX_COMPILER_LAUNCHER=sccache',
                                         '-DLLVM_ENABLE_ZLIB=OFF',
-                                        '-DLLVM_LIT_TOOLS_DIR="C:\\Program Files\\GnuWin32\\usr\\bin"',
+                                        '-DLLVM_LIT_TOOLS_DIR=C:\\Program Files\\GnuWin32\\usr\\bin',
                                         ])},
 
 # Flang builders.