utils: correct flag handling for static runtime libdispatch handling

We were not passing along the proper flags to the runtime build
resulting in the library expecting libdispatch to be linked dynamically.

Author: compnerd

utils/build.ps1

@@ -2357,7 +2357,8 @@ function Build-ExperimentalRuntime {
         CMAKE_Swift_COMPILER_TARGET = (Get-ModuleTriple $Platform);
         CMAKE_Swift_COMPILER_WORKS = "YES";
         # TODO(compnerd) enforce dynamic linking of BlocksRuntime and dispatch.
-        CMAKE_Swift_FLAGS = $(if ($Static) { @("-Xcc", "-static-libclosure", "-Xcc", "-Ddispatch_STATIC") } else { @() });
+        CMAKE_CXX_FLAGS = $(if ($Static) { @("-Ddispatch_STATIC") } else { @() });
+        CMAKE_Swift_FLAGS = $(if ($Static) { @("-Xcc", "-static-libclosure") } else { @() });
         CMAKE_STATIC_LIBRARY_PREFIX_Swift = "lib";
         CMAKE_SYSTEM_NAME = $Platform.OS.ToString();
         CMAKE_NINJA_FORCE_RESPONSE_FILE = "YES";
@@ -2762,8 +2763,7 @@ function Build-ExperimentalSDK([Hashtable] $Platform) {
         CMAKE_FIND_PACKAGE_PREFER_CONFIG = "YES";
         CMAKE_Swift_COMPILER_TARGET = (Get-ModuleTriple $Platform);
         CMAKE_Swift_COMPILER_WORKS = "YES";
-        # TODO(compnerd) enforce dynamic linking of BlocksRuntime and dispatch.
-        CMAKE_Swift_FLAGS = @("-static-stdlib", "-Xfrontend", "-use-static-resource-dir", "-Xcc", "-Ddispatch_STATIC");
+        CMAKE_Swift_FLAGS = @("-static-stdlib", "-Xfrontend", "-use-static-resource-dir");
         CMAKE_STATIC_LIBRARY_PREFIX_Swift = "lib";
         CMAKE_SYSTEM_NAME = $Platform.OS.ToString();