disk: part: refactor generic name creation for DOS and ISO

In both DOS and ISO partition tables the same code to create partition name
like "hda1" was repeated.

Code moved to into a new function part_set_generic_name() in part.c and optimized.
Added recognition of MMC and SD types, name is like "mmcsda1".

Signed-off-by: Petr Kulhavy <brain@jikos.cz>
Reviewed-by: Tom Rini <trini@konsulko.com>
Acked-by: Steve Rae <steve.rae@raedomain.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/disk/part_iso.c b/disk/part_iso.c
index 78fc97e..bb8ed65 100644
--- a/disk/part_iso.c
+++ b/disk/part_iso.c
@@ -137,30 +137,7 @@
 	entry_num=1;
 	offset=0x20;
 	strcpy((char *)info->type, "U-Boot");
-	switch(dev_desc->if_type) {
-		case IF_TYPE_IDE:
-		case IF_TYPE_SATA:
-		case IF_TYPE_ATAPI:
-			sprintf ((char *)info->name, "hd%c%d",
-				'a' + dev_desc->devnum, part_num);
-			break;
-		case IF_TYPE_SCSI:
-			sprintf ((char *)info->name, "sd%c%d",
-				'a' + dev_desc->devnum, part_num);
-			break;
-		case IF_TYPE_USB:
-			sprintf ((char *)info->name, "usbd%c%d",
-				'a' + dev_desc->devnum, part_num);
-			break;
-		case IF_TYPE_DOC:
-			sprintf ((char *)info->name, "docd%c%d",
-				'a' + dev_desc->devnum, part_num);
-			break;
-		default:
-			sprintf ((char *)info->name, "xx%c%d",
-				'a' + dev_desc->devnum, part_num);
-			break;
-	}
+	part_set_generic_name(dev_desc, part_num, (char *)info->name);
 	/* the bootcatalog (including validation Entry) is limited to 2048Bytes
 	 * (63 boot entries + validation entry) */
 	 while(offset<2048) {