Configure: ensure that a DEPEND generates the correct inclusion directory

Configure: ensure that a DEPEND generates the correct inclusion directory

We incorrectly assumed that explicit dependencies meant that the
source directory would be added for inclusion.  However, if the
dependent file is generated, it's stored in the build directory, and
that should be used for inclusion rather than the source directory.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5153)

(cherry picked from commit e431bcfabd72163b0ee89674e2face26a349ba9c)