arm64: hibernate: variable pudp is used instead of pd4dp

There should be p4dp used when p4d page is allocated.
This is not a functional issue, but for the logical correctness this
should be fixed.

Fixes: e9f63768 ("arm64: add support for folded p4d page tables")
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/r/20210125191923.1060122-3-pasha.tatashin@soleen.com


Signed-off-by: Will Deacon <will@kernel.org>