ide: add device flags

Add 'unsigned long dev_flags' to ide_drive_t and convert bitfields
to IDE_DFLAG_* flags.

While at it:
- IDE_DFLAG_ADDRESSING -> IDE_DFLAG_LBA48
- fixup some comments
- remove needless g->flags zeroing from ide*_probe()

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-lib.c b/drivers/ide/ide-lib.c
index ed426dd..9fc4cfb 100644
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -317,7 +317,7 @@
 {
 	ide_task_t task;
 	struct ide_taskfile *tf = &task.tf;
-	int lba48 = (drive->addressing == 1) ? 1 : 0;
+	u8 lba48 = !!(drive->dev_flags & IDE_DFLAG_LBA48);
 
 	memset(&task, 0, sizeof(task));
 	if (lba48)