zdump: Drop non-extended multi-volume DASD dump support

Since DASD standalone dumper does not support non-extended s390
multi-volume dumps for years, drop zgetdump support of non-extended s390_mv
DASD dumps and dump-tools:
- Merge dfi_s390mv_ext and dt_s390mv_ext with related dfi_s390mv and
  dt_s390mv counterparts.
- Update DFI and DT vectors of supported dump formats and dump-tools
  removing dfi_s390mv and dt_s390mv entries and keeping dt_s390mv_ext and
  dfi_s390mv_ext ones for s390_mv extended dump and dump-tool accordingly.
- Remove dfi_s390mv.c and dt_s390mv.c sources and update the Makefile.
- Make dfi_s390mv_ext_init() and dfi_s390mv_info() static.
- Remove magic number relevant to non-extended s390_mv DASD dumper.
- Completely drop DASD dumper version 5 case in df_s390_dumper_read().

Note: Since non-extended s390 multi-volume dumps can reside on DASD
partitions only and cannot be produced via DFO interface, we can drop this
dump format entirely.

Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

zdump/dfi.c

@@ -30,7 +30,6 @@ static struct dfi *dfi_vec[] = {
 	&dfi_s390tape,
 	&dfi_devmem,
 	&dfi_s390mv_ext,
-	&dfi_s390mv,
 	&dfi_s390_ext,
 	&dfi_s390,
 	&dfi_lkcd,