[embedded] Also build Concurrency module for x86_64

Author: kubamracek

stdlib/public/Concurrency/CMakeLists.txt

@@ -280,7 +280,7 @@ if(SWIFT_SHOULD_BUILD_EMBEDDED_STDLIB AND SWIFT_SHOULD_BUILD_EMBEDDED_CONCURRENC
         continue()
       endif()
     elseif (SWIFT_HOST_VARIANT STREQUAL "macosx")
-      if(NOT "${mod}" MATCHES "arm64|arm64e|armv7|armv7m|armv7em")
+      if(NOT "${mod}" MATCHES "x86_64|arm64|arm64e|armv7|armv7m|armv7em")
         continue()
       endif()