Fix: passed to proc after free
Fix: passed to proc after free

Found by static analyzer svace
Static analyzer message: Pointer 'dp' is passed to a function at
iter_hints.c:401 after the referenced memory was deallocated at
iter_hints.c:174 by passing as 3rd parameter to function 'hints_insert'
at iter_hints.c:398.

on-behalf-of: @ideco-team <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@ideco.ru>

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