headers/build: Replace StackOrHeapArray with a reference to the main one.

The files were identical. No functional change.

tools/locale: Fix using auto_ptr to array.

Use BStackOrHeapArray instead of using auto_ptr to array.

Change-Id: I171cb002829c36ec51ba7d1e387869263e2a40f2
Reviewed-on: https://review.haiku-os.org/745
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>