Use versioned override hooks for the concurrency runtime

Author: DougGregor

stdlib/public/CompatibilityOverride/CompatibilityOverride.h

@@ -90,7 +90,7 @@ namespace swift {
 // resolve to string literal containing the appropriate section name for the
 // current library.
 #define COMPATIBILITY_OVERRIDE_SECTION_NAME_swiftRuntime "__swift57_hooks"
-#define COMPATIBILITY_OVERRIDE_SECTION_NAME_swift_Concurrency "__s_async_hook"
+#define COMPATIBILITY_OVERRIDE_SECTION_NAME_swift_Concurrency "__s57async_hook"
 
 #define COMPATIBILITY_OVERRIDE_SECTION_NAME                                    \
   COMPATIBILITY_CONCAT(COMPATIBILITY_OVERRIDE_SECTION_NAME_,                   \

unittests/runtime/CompatibilityOverrideConcurrency.cpp

@@ -55,7 +55,7 @@ struct OverrideSection {
 };
 
 OverrideSection ConcurrencyOverrides
-    __attribute__((section("__DATA,__s_async_hook"))) = {
+    __attribute__((section("__DATA,__s57async_hook"))) = {
         0,
 #define OVERRIDE(name, ret, attrs, ccAttrs, namespace, typedArgs, namedArgs)   \
   name##Override,