NUCEXT RENAME plist is processed incorrectly, uses wrong newname

[RossPatterson]

The NUCEXT RENAME macro invokes DMSSNX to rename a nucleus extension. The plist is documented in DMSSNX ASSEMBLE as:

*         5) Rename a nucleus extension
*            DC  CL8'NUCEXT'
*            DC  CL8'oldname'   old name of the nucleus ext
*            DC  4X'00'         reserved
*            DC  AL4(2)         identifies the rename function
*            DC  CL8'newname'   new name for the extension
*            DC  8X'FF'         fence

The NUCEXT macro correctly creates this plist:

                                     155          NUCEXT RENAME,NAME='DMSNXL',NEW='NUCXLOAD',                   *
                                                        ERROR=1,MF=(E,WRKNXRPL) Rename the NUCXTEXT'd DMSNXL.
 000140 4110 D058      00058         156+         LA    1,WRKNXRPL         Point to list form                    01730000
 000144 D207 1000 CD50 00000 00D50   157+         MVC   0(8,1),=CL8'NUCEXT'                             RAP009DS 01790100
 00014A D207 1008 CD58 00008 00D58   158+         MVC   8(8,1),=CL8'DMSNXL' Set name                             02280000
 000150 D703 1010 1010 00010 00010   159+         XC    16(4,1),16(1)                                            04740000
 000156 D203 1014 CD68 00014 00D68   160+         MVC   20(4,1),=F'2'         Rename                             04750000
 00015C D207 1018 CCE8 00018 00CE8   161+         MVC   24(8,1),=CL8'NUCXLOAD' Set new name                      04820000
 000162 0ACA                         162+         SVC   202                Process the call                      05140000
 000164 00000001                     163+         DC    AL4(1)             Error processing address              05220000

The code in DMSSNX, however, thinks the newname field (SUBNAME2 below) is 4 bytes later in the plist than it is, leading to the wrong name after the operation:

SUBPLIST DSECT                SUBCOM plist
         DC    CL8'SUBCOM'    CL8'SUBCOM' or CL8'NUCEXT'
SUBPNAME DS    CL8            Name
SUBRETN  DS    A              Pass back pointer for QUERY/ANCHOR
SUBFUNC  DS    F              Function call type
         ORG   SUBRETN
SUBPSW   DS    0D             Starting PSW
SUBMASK  DS    X              System Mask
SUBKEY   DS    X              Storage Key
SUBPFLAG DS    X              Flags                            HRC424DS
SUBPSEG  EQU   X'20'          Segment resident                 HRC424DS
SUBUSRF  DS    X              User Flags
SUBADDR  DS    A              Entry point
SUBWKRD  DS    A              Work area (If any)
SUBXORG  DS    A              Origin (for NUCEXT)
SUBXLEN  DS    F              Length (for NUCEXT)
SUBSEGID DS    CL8            Segment name (for NUCEXT)        HRC424DS
         ORG   SUBXORG                                         
SUBNAME2 DS    CL8            Second SCBLOCK name for RENAME

[RossPatterson]

Fix is:
DMSSNX AUXLCL:

RAP011DS PE HRC404DS Wrong newname plist location for NUCEXT RENAME.

DMSSNX RAP011DS:

./ R  09270000 09270000 $
         ORG   SUBWKRD                                         RAP011DS