lightnvm: pblk: fix bad le64 assignations

Use the right types and conversions on le64 variables. Reported by
sparse.

Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <matias@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/lightnvm/pblk-map.c b/drivers/lightnvm/pblk-map.c
index a9be03cd..fddb924 100644
--- a/drivers/lightnvm/pblk-map.c
+++ b/drivers/lightnvm/pblk-map.c
@@ -53,7 +53,7 @@ static void pblk_map_page_data(struct pblk *pblk, unsigned int sentry,
 			lba_list[paddr] = cpu_to_le64(w_ctx->lba);
 			line->nr_valid_lbas++;
 		} else {
-			u64 addr_empty = cpu_to_le64(ADDR_EMPTY);
+			__le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
 
 			lba_list[paddr] = meta_list[i].lba = addr_empty;
 			__pblk_map_invalidate(pblk, line, paddr);