cmd: part: number: return hexadecimal value

At this point we are using part number sub-command to retrieve UUID
of the partition using it's name.

e.g.:
 part number mmc $mmcdev system_a system_a_index
 part uuid mmc $mmcdev:${system_a_index} system_a_uuid

Since 'part uuid' sub-command expects partition index in hex format and
'part number' returns decimal value, 'part uuid' command will provide
wrong UUID or fail.

Fixes: be683756 ("cmd: part: Add 'number' sub-command")
Cc: Dirk Behme <dirk.behme@de.bosch.com>
Reported-by: NPontus Fuchs <pontus.fuchs@se.bosch.com>
Signed-off-by: NRoman Stratiienko <roman.stratiienko@globallogic.com>
Signed-off-by: NEugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: NTom Rini <trini@konsulko.com>
Reviewed-by: NIgor Opaniuk <igor.opaniuk@gmail.com>

cmd/part.c

@@ -152,7 +152,7 @@ static int do_part_info(int argc, char * const argv[], enum cmd_part_info param)
 		snprintf(buf, sizeof(buf), LBAF, info.size);
 		break;
 	case CMD_PART_INFO_NUMBER:
-		snprintf(buf, sizeof(buf), "%d", part);
+		snprintf(buf, sizeof(buf), "0x%x", part);
 		break;
 	default:
 		printf("** Unknown cmd_part_info value: %d\n", param);