Remove BK files for DB2

when you deleting bk files for Database, don't forget to deleting Backup records in SYSIBM.SYSCOPY tables.

//*********************************************************************
//*THE MODIFY UTILITY WITH THE RECOVERY OPTION DELETES RECORDS FROM THE
//*SYSIBM.SYSCOPY CATALOG TABLE, RELATED LOG RECORDS FROM THE
//*SYSIBM.SYSLGRNX DIRECTORY TABLE, AND ENTRIES FROM THE DBD, AND
//*RECYCLES DB2? VERSION NUMBERS FOR REUSE.
//*********************************************************************
//UTILSTEP EXEC PGM=DSNUTILB,
// PARM=(D61A,FMSTHP,''),
// TIME=1440,REGION=0M
//STEPLIB DD DSN=DSN810.SDSNLOAD,DISP=SHR
//DSNTRACE DD SYSOUT=*
//SYSTSPRT DD SYSOUT=*
//SYSPRINT DD SYSOUT=*
//UTPRINT DD SYSOUT=*
//SYSUDUMP DD SYSOUT=*
//SYSABEND DD SYSOUT=*
//SYSUT1 DD UNIT=(SYSDA,1),SPACE=(CYL,10)
//*DELETING SYSCOPY AND SYSLGRNX RECORDS THAT ARE OVER A CERTAIN AGE
//SYSIN DD *
MODIFY RECOVERY TABLESPACE DSN8D91A.DSN8S91E DELETE AGE(90)
/*
//