Dpkg::Source::Package::V1: Disable upstream tar signature when building

The current stable dpkg series does not support extracting upstream tar
signatures. So let's disable this for now until either those are
supported in 1.17.x or 1.18.x, and we'll be able to enable them again
in 1.18.x or 1.19.x respectively.

debian/changelog

@@ -74,6 +74,9 @@ dpkg (1.18.8) UNRELEASED; urgency=medium
       Closes: #823805
     - Check whether dependency restrictions are implied in Dpkg::Deps::Simple.
       Thanks to Ben Hutchings <ben@decadent.org.uk>. Closes: #827633
+    - Disable upstream tar signature when building format 1.0 source packages
+      in Dpkg::Source::Package::V1, as the current stable dpkg series do not
+      support extracting them.
   * Test suite:
     - Bump perlcritic ValuesAndExpressions::RequireNumberSeparators minimum
       to 99999.

scripts/Dpkg/Source/Package/V1.pm

@@ -405,7 +405,9 @@ sub do_build {
     }
 
     $self->add_file($tarname) if $tarname;
-    $self->add_file($tarsign) if $tarsign and -e $tarsign;
+    # XXX: Reenable once a stable dpkg supports extracting upstream signatures
+    # for source 1.0 format, either in 1.17.x or 1.18.x.
+    #$self->add_file($tarsign) if $tarsign and -e $tarsign;
 
     if ($sourcestyle =~ m/[kpKP]/) {
         if (stat($origdir)) {