ide: add IDE_HFLAG_DTC2278 host flag

Add IDE_HFLAG_DTC2278 host flag and use it instead of ide_dtc2278
chipset type in ide_init_port().

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 901d323..732a05f 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -1325,6 +1325,8 @@
 	IDE_HFLAG_ERROR_STOPS_FIFO	= (1 << 19),
 	/* serialize ports */
 	IDE_HFLAG_SERIALIZE		= (1 << 20),
+	/* host is DTC2278 */
+	IDE_HFLAG_DTC2278		= (1 << 21),
 	/* host is TRM290 */
 	IDE_HFLAG_TRM290		= (1 << 23),
 	/* use 32-bit I/O ops */