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

arch/arm64/kernel/hibernate.c

@@ -190,10 +190,10 @@ static int trans_pgd_map_page(pgd_t *trans_pgd, void *page,
 
 	pgdp = pgd_offset_pgd(trans_pgd, dst_addr);
 	if (pgd_none(READ_ONCE(*pgdp))) {
-		pudp = (void *)get_safe_page(GFP_ATOMIC);
-		if (!pudp)
+		p4dp = (void *)get_safe_page(GFP_ATOMIC);
+		if (!pgdp)
 			return -ENOMEM;
-		pgd_populate(&init_mm, pgdp, pudp);
+		pgd_populate(&init_mm, pgdp, p4dp);
 	}
 
 	p4dp = p4d_offset(pgdp, dst_addr);