ps3vram: use bvec_virt

Use bvec_virt instead of open coding it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210804095634.460779-13-hch@lst.deSigned-off-by: NJens Axboe <axboe@kernel.dk>

drivers/block/ps3vram.c

@@ -541,7 +541,7 @@ static struct bio *ps3vram_do_bio(struct ps3_system_bus_device *dev,
 
 	bio_for_each_segment(bvec, bio, iter) {
 		/* PS3 is ppc64, so we don't handle highmem */
-		char *ptr = page_address(bvec.bv_page) + bvec.bv_offset;
+		char *ptr = bvec_virt(&bvec);
 		size_t len = bvec.bv_len, retlen;
 
 		dev_dbg(&dev->core, "    %s %zu bytes at offset %llu\n", op,