docs: Prepare for new sub tree

See #11925

docs/content/en/functions/fmt/Errorf.md

@@ -1,26 +0,0 @@
----
-title: fmt.Errorf
-description: Log an ERROR from a template.
-categories: []
-keywords: []
-action:
-  aliases: [errorf]
-  related:
-    - functions/fmt/Erroridf
-    - functions/fmt/Warnf
-  returnType: string
-  signatures: ['fmt.Errorf FORMAT [INPUT]']
-aliases: [/functions/errorf]
----
-
-{{% include "functions/fmt/_common/fmt-layout.md" %}}
-
-The `errorf` function evaluates the format string, then prints the result to the ERROR log and fails the build.
-
-```go-html-template
-{{ errorf "The %q shortcode requires a src parameter. See %s" .Name .Position }}
-```
-
-Use the [`erroridf`] function to allow optional suppression of specific errors.
-
-[`erroridf`]: /functions/fmt/erroridf