cmake: treat unregistered components as unresolved

tools/cmake/build.cmake

@@ -181,7 +181,8 @@ endfunction()
 #
 function(__build_resolve_and_add_req var component_target req type)
     __component_get_target(_component_target ${req})
-    if(NOT _component_target)
+    __component_get_property(_component_registered ${component_target} __COMPONENT_REGISTERED)
+    if(NOT _component_target OR NOT _component_registered)
         message(FATAL_ERROR "Failed to resolve component '${req}'.")
     endif()
     __component_set_property(${component_target} ${type} ${_component_target} APPEND)