[libc++] Remove the libc++ Sphinx docs job

It is now redundant, since we do it in the BuildKite jobs.

Differential Revision: https://reviews.llvm.org/D92861
diff --git a/buildbot/osuosl/master/config/builders.py b/buildbot/osuosl/master/config/builders.py
index d995925..1e0ccc2 100644
--- a/buildbot/osuosl/master/config/builders.py
+++ b/buildbot/osuosl/master/config/builders.py
@@ -1515,12 +1515,6 @@
     'builddir': "lldb-sphinx-docs",
     'factory' : SphinxDocsBuilder.getSphinxDocsBuildFactory(lldb_html=True)},
 
-    {'name':"libcxx-sphinx-docs",
-    'tags'  : ["libcxx", "doc"],
-    'workernames':["gribozavr3"],
-    'builddir':"libcxx-sphinx-docs",
-    'factory': SphinxDocsBuilder.getSphinxDocsBuildFactory(libcxx_html=True)},
-
     {'name':"libunwind-sphinx-docs",
     'tags'  : ["libunwind", "doc"],
     'workernames':["gribozavr3"],