Don't fail when building architecture all packages only. Closes: #906595

debian/rules

@@ -12,5 +12,5 @@ override_dh_missing:
 
 override_dh_fixperms:
 	dh_fixperms
-	chmod u+s \
-		debian/clevis-udisks2/usr/lib/*/clevis-luks-udisks2
+	find debian/clevis-udisks2/usr/lib/*/clevis-luks-udisks2 -type f -print0 | \
+		xargs -r0 chmod u+s