nvmet: use PAGE_SECTORS_SHIFT

Replace occurences of the pattern "PAGE_SHIFT - 9" in the passthru and
loop targets with PAGE_SECTORS_SHIFT.

Signed-off-by: Damien Le Moal <[e-mail]>
Reviewed-by: Chaitanya Kulkarni <[e-mail]>
Reviewed-by: Sagi Grimberg <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
Signed-off-by: Keith Busch <[e-mail]>

drivers/nvme/target/loop.c

···
 		goto out_cleanup_tagset;
 
 	ctrl->ctrl.max_hw_sectors =
-		(NVME_LOOP_MAX_SEGMENTS - 1) << (PAGE_SHIFT - 9);
+		(NVME_LOOP_MAX_SEGMENTS - 1) << PAGE_SECTORS_SHIFT;
 
 	nvme_unquiesce_admin_queue(&ctrl->ctrl);
 

drivers/nvme/target/passthru.c

···
 	 * which depends on the host's memory fragementation. To solve this,
 	 * ensure mdts is limited to the pages equal to the number of segments.
 	 */
-	max_hw_sectors = min_not_zero(pctrl->max_segments << (PAGE_SHIFT - 9),
+	max_hw_sectors = min_not_zero(pctrl->max_segments << PAGE_SECTORS_SHIFT,
 				      pctrl->max_hw_sectors);
 
 	/*
 	 * nvmet_passthru_map_sg is limitted to using a single bio so limit
 	 * the mdts based on BIO_MAX_VECS as well
 	 */
-	max_hw_sectors = min_not_zero(BIO_MAX_VECS << (PAGE_SHIFT - 9),
+	max_hw_sectors = min_not_zero(BIO_MAX_VECS << PAGE_SECTORS_SHIFT,
 				      max_hw_sectors);
 
 	page_shift = NVME_CAP_MPSMIN(ctrl->cap) + 12;