Remove outdated svn/git information from hacking page

The patch files section is redundant to https://llvm.org/docs/GettingStarted.html.
There is nothing clang specific here. We are talking about a monorepo after all.
While it may seem nice to have one single clang page which explains everything,
it's not: It doesn't cover the topics in sufficient depth, it's redundant to
other pages and it's hard to keep it up to date as we see with the svn
instructions.

diff --git a/clang/www/hacking.html b/clang/www/hacking.html
index fbcf88b..3623b90 100755 (executable)
--- a/clang/www/hacking.html
+++ b/clang/www/hacking.html
@@ -275,30 +275,8 @@ Testing Time: 81.52s
   <h2 id="patches">Creating Patch Files</h2>
   <!--=====================================================================-->
 
-  <p>To return changes to the Clang team, unless you have checkin
-  privileges, the preferred way is to send patch files
-  <a href="https://llvm.org/docs/Contributing.html#how-to-submit-a-patch">using LLVM's Phabricator</a> with an explanation of what the patch is for. Clang follows <a
-  href="https://llvm.org/docs/DeveloperPolicy.html">LLVM's developer policy</a>.
-  If your patch requires a wider discussion (for example, because it is an
-  architectural change), you can use the cfe-dev mailing list.</p>
-
-  <p>To create these patch files, change directory
-  to the llvm/tools/clang root and run:</p>
-
-  <pre>svn diff (relative path) >(patch file name)</pre>
-
-  <p>For example, for getting the diffs of all of clang:</p>
-
-  <pre>svn diff . >~/mypatchfile.patch</pre>
-
-  <p>For example, for getting the diffs of a single file:</p>
-
-  <pre>svn diff lib/Parse/ParseDeclCXX.cpp >~/ParseDeclCXX.patch</pre>
-
-  <p>Note that the paths embedded in the patch depend on where you run it,
-  so changing directory to the llvm/tools/clang directory is recommended.</p>
-
-  <p>It is also possible to <a href="https://llvm.org/docs/GettingStarted.html#sending-patches-with-git">use git to contribute</a> to Clang.</p>
+  <p>To contribute changes to Clang see
+    <a href="https://llvm.org/docs/GettingStarted.html#sending-patches">LLVM's Getting Started page</a></p>
 
   <!--=====================================================================-->
   <h2 id="irgen">LLVM IR Generation</h2>