Remove empty 3.0-migration-guide.d

This is now captured in 3.0-migration-guide.md

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/docs/3.0-migration-guide.d/00README b/docs/3.0-migration-guide.d/00README
deleted file mode 100644
index a41733e..0000000
--- a/docs/3.0-migration-guide.d/00README
+++ /dev/null
@@ -1,27 +0,0 @@
-Please add your migration guide entries here. Until 3.0 is released, each PR
-that makes backwards-incompatible changes should add a file here, with the
-extension .md, a descriptive name and the following format:
-
----%<------%<------%<------%<------%<------%<------%<------%<---
-
-The change that was made
-------------------------
-
-Who exactly is affected: does this affect users of the default config, of a
-particular feature? Remember to contextualise.
-
-If I'm affected, what's my migration path? How should I change my code if this
-is an API change; if a feature was removed what are my alternatives?
-
----%<------%<------%<------%<------%<------%<------%<------%<---
-
-PRs that make multiple independent changes should include one entry for each
-changes or logical groups of changes. You can either add multiple files or put
-multiple entries in the same file.
-
-For examples, have a look a docs/3.0-migration-guide.md (which includes the
-top-level header and an intro before the list of entries).
-
-As part of release preparation, the entries in this directory will be appended
-to docs/3.0-migration-guide.md and then re-ordered and reviewed one last time.
-The file is then going to be moved to the version-independent docs repo.