of: unittest: Fix EXPECT for parse_phandle_with_args_map() test

Commit 12e17243 ("of: base: improve error msg in
of_phandle_iterator_next()") added printing of the phandle value on
error, but failed to update the unittest.

Fixes: 12e17243 ("of: base: improve error msg in of_phandle_iterator_next()")
Cc: stable@vger.kernel.org
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230801-dt-changeset-fixes-v3-1-5f0410e007dd@kernel.org


Signed-off-by: Rob Herring <robh@kernel.org>