Bootstrapping: copy all the legacy layouts for the host platforms

The bootstrapping compilers may be used for cross compilation, so we
need to ensure to have legacy layouts for all the architectures.

Addresses rdar://98899578

Author: edymtt

stdlib/toolchain/legacy_layouts/CMakeLists.txt

@@ -56,9 +56,16 @@ foreach(sdk ${SWIFT_SDKS})
 endforeach()
 
 if(${BOOTSTRAPPING_MODE} MATCHES "BOOTSTRAPPING.*")
-  # Bootstrapping - level 0
-  add_layout_copying( ${SWIFT_HOST_VARIANT_SDK} ${SWIFT_HOST_VARIANT_ARCH} "0")
+  # The bootstrapping compilers may be used to cross compile
+  # for other architectures, so we would need the matching
+  # resource directories to have all the legacy layouts
+  foreach(arch
+          ${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_ARCHITECTURES}
+          ${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_MODULE_ARCHITECTURES})
+    # Bootstrapping - level 0
+    add_layout_copying( ${SWIFT_HOST_VARIANT_SDK} ${arch} "0")
 
-  # Bootstrapping - level 1
-  add_layout_copying( ${SWIFT_HOST_VARIANT_SDK} ${SWIFT_HOST_VARIANT_ARCH} "1")
+    # Bootstrapping - level 1
+    add_layout_copying( ${SWIFT_HOST_VARIANT_SDK} ${arch} "1")
+  endforeach()
 endif()