dselect: Remove unnecessary handling of obsolete Package_Revision field

This is automatically handled by «dpkg-deb --field» now that it uses
the libdpkg deb822 parser.

debian/changelog

@@ -22,6 +22,8 @@ dpkg (1.17.14) UNRELEASED; urgency=low
   * Fix order of Files field on generated .changes file in dpkg-genchanges.
     Regression introduced in dpkg 1.17.7.
   * Stop warning on unknown arbitrary fields from dpkg-deb.
+  * Remove unnecessary handling of obsolete Package_Revision field in dselect
+    ftp method.
 
   [ Raphaël Hertzog ]
   * Explain better in deb-triggers(5) why interest/activate-noawait should be

dselect/methods/ftp/install

@@ -474,7 +474,6 @@ sub getdebinfo($) {
 	close($pkgfile_fh);
 	$pkg = $fields{'package'};
 	$ver = $fields{'version'};
-	if($fields{'package_revision'}) { $ver .= '-' . $fields{'package_revision'}; }
 	return $pkg, $ver;
     } elsif ( $type == 2) {
 	open(my $pkgfile_fh, '-|', "dpkg-split --info $fn")