Mass rename C1x references to C11. The name hasn't proliferated like "C++0x" so this patch is surprisingly small.

Also drop -Wc1x-extensions in favor of -Wc11-extensions. I don't think we need to keep this around for compatibility.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147221 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index 58e16bf..5bae0e4 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -573,20 +573,20 @@
                                        IsTypeName, TypenameLoc);
 }
 
-/// ParseStaticAssertDeclaration - Parse C++0x or C1X static_assert-declaration.
+/// ParseStaticAssertDeclaration - Parse C++0x or C11 static_assert-declaration.
 ///
 /// [C++0x] static_assert-declaration:
 ///           static_assert ( constant-expression  ,  string-literal  ) ;
 ///
-/// [C1X]   static_assert-declaration:
+/// [C11]   static_assert-declaration:
 ///           _Static_assert ( constant-expression  ,  string-literal  ) ;
 ///
 Decl *Parser::ParseStaticAssertDeclaration(SourceLocation &DeclEnd){
   assert((Tok.is(tok::kw_static_assert) || Tok.is(tok::kw__Static_assert)) &&
          "Not a static_assert declaration");
 
-  if (Tok.is(tok::kw__Static_assert) && !getLang().C1X)
-    Diag(Tok, diag::ext_c1x_static_assert);
+  if (Tok.is(tok::kw__Static_assert) && !getLang().C11)
+    Diag(Tok, diag::ext_c11_static_assert);
   if (Tok.is(tok::kw_static_assert))
     Diag(Tok, diag::warn_cxx98_compat_static_assert);