efi_loader: correct parameter size in efi_allocate_pool

efi_allocate_pages() expects a (uint64_t *) pointer to pass the address of
the assigned memory. If we pass the address of a pointer here, an illegal
memory access occurs on 32bit systems.

Fixes: 282a06cbcae8 ("efi_loader: Expose U-Boot addresses in memory map
for sandbox")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
index ebd2b36..55622d2 100644
--- a/lib/efi_loader/efi_memory.c
+++ b/lib/efi_loader/efi_memory.c
@@ -440,6 +440,7 @@
 efi_status_t efi_allocate_pool(int pool_type, efi_uintn_t size, void **buffer)
 {
 	efi_status_t r;
+	u64 addr;
 	struct efi_pool_allocation *alloc;
 	u64 num_pages = efi_size_in_pages(size +
 					  sizeof(struct efi_pool_allocation));
@@ -453,9 +454,9 @@
 	}
 
 	r = efi_allocate_pages(EFI_ALLOCATE_ANY_PAGES, pool_type, num_pages,
-			       (uint64_t *)&alloc);
-
+			       &addr);
 	if (r == EFI_SUCCESS) {
+		alloc = (struct efi_pool_allocation *)(uintptr_t)addr;
 		alloc->num_pages = num_pages;
 		*buffer = alloc->data;
 	}