Command/Packaging.pm: cme_fix_dpkg_control: drop DUMMY workaround

and use proper parameter for forcing a save even without changes to get
C::M's reformatting.

Thanks: dod for pointing me to the correct way to do this
Gbp-Dch: Ignore
6 jobs for post-buster in 9 minutes and 20 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #195858
build

00:03:16

 
  Test
passed #195861
autopkgtest

00:06:03

passed #195862
blhc

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passed #195860
lintian

00:01:54

passed #195863
piuparts

00:06:00

passed #195859
reprotest

00:03:55