Merge wpiformat configs (#8365)

After replacing the remaining include guards with `#pragma once`, I was
able to merge all the wpiformat configs into one file in the repo root.
This should make the config easier to reason about and maintain in the
future.

ntcoreffi/.styleguide

@@ -1,20 +0,0 @@
-cppHeaderFileInclude {
-  \.h$
-  \.hpp$
-}
-
-cppSrcFileInclude {
-  \.cpp$
-}
-
-modifiableFileExclude {
-  src/main/native/include/DataLogManager\.h$
-}
-
-repoRootNameOverride {
-  ntcoreffi
-}
-
-includeGuardRoots {
-  ntcoreffi/src/main/native/include/
-}