Give 'fixit-cxx0x.cpp' a more modern name.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@361208 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/FixIt/fixit-cxx0x.cpp b/test/FixIt/fixit-c++11.cpp
similarity index 100%
rename from test/FixIt/fixit-cxx0x.cpp
rename to test/FixIt/fixit-c++11.cpp