[NCO Bug] Remove misleading "No such file or directory" syntax errors from output files

[KateFriedman-NOAA]

Bugzilla #1369

Details from bugzilla:

From NCO SPA:

In the output logs for gfs/gdas/enkfgdas there are hundres of instances of "No such file or directory" messages 
printed out across many different tasks, which makes it more difficult to troubleshoot production failures.
Please work towards removing all related syntax errors from the output logs

A list of tasks from the 12z cycle found with these messages:
enkfgdas_diag_12
enkfgdas_fcst_??_12
gdas_atmos_analysis_diag_12
gdas_atmos_tropcy_qc_reloc_12
gdas_atmos_verfozn_12
gdas_atmos_verfrad_12
gdas_forecast_12
gfs_atmos_gempak_meta_12
gfs_atmos_tropcy_qc_reloc_12
gfs_atmos_wafs_grib2_0p25_12
gfs_atmos_wafs_grib2_12
gfs_mos_ext_grd_prdgen_12
gfs_mos_ext_grd_prep_12
gfs_mos_ext_stn_fcst_12
gfs_mos_ext_stn_prdgen_12
gfs_mos_ext_stn_prep_12
gfs_mos_grd_fcst_12
gfs_mos_grd_prdgen_12
gfs_mos_stn_fcst_12
gfs_mos_stn_prdgen_12
gfs_mos_wx_ext_prdgen_12
gfs_mos_wx_prdgen_12
gfs_wave_prdgen_gridded_12

Comment from @RussTreadon-NOAA:

A check of the gdas_atmos_analysis_diag and enkfgdas_diag "No such file" messages shows that the messages 
originate from the same script, exglobal_diag.sh.  The following loop is responsible for generating the 
"No such file" messages

   # Restrict diagnostic files containing rstprod data
   rlist="conv_gps conv_ps conv_pw conv_q conv_sst conv_t conv_uv saphir"
   for rtype in $rlist; do
       ${CHGRP_CMD} *${rtype}*
   done

A check on file existence can be added to ensure ${CHGRP_CMD} is only executed when ${rtype} exists.

For GFS v16.3 exgdas_diag.sh resides in NOAA-EMC/GSI branch release/gfsda.v16.3.0.  Note that NOAA-EMC/GSI 
develop no longer maintains DA jobs or scripts.  GFS DA jobs and scripts are now maintained in the 
global-workflow repository.  Therefore, add Rahul Mahajan to the cc list for this bugzilla.

Comment from Steven Earle:

gfs_mos tasks are excluded from this... but please do a thorough review of all gfs/gdas/enkf tasks for 
version 17... we need to work toward remove all false/misleading errors from our output.