Add links to cross-compilation docs from getting started

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191425 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/GettingStarted.rst b/docs/GettingStarted.rst
index 5ce1893..5c36952 100644
--- a/docs/GettingStarted.rst
+++ b/docs/GettingStarted.rst
@@ -930,6 +930,10 @@
 The result of such a build is executables that are not runnable on on the build
 host (--build option) but can be executed on the compile host (--host option).
 
+Check :doc:`HowToCrossCompileLLVM` and `Clang docs on how to cross-compile in general
+<http://clang.llvm.org/docs/CrossCompilation.html>`_ for more information
+about cross-compiling.
+
 The Location of LLVM Object Files
 ---------------------------------