Fix gcc-7 and gcc-8 build of GO for Hurd and not kFreeBSD in debian/rules.defs

[Svante Signell <svante dot signell at gmail dot com>]

On Thu, 2017-11-16 at 20:39 +0100, Svante Signell wrote:

Seeing the recent update of debian/rules.defs in gcc-7 a mistake was revealed in
the patch debian_rules.defs for both gcc-7 and gcc-8. The correct patch is
inlined below:

--- a/debian/rules.defs	2017-11-20 12:59:25.000000000 +0100
+++ b/debian/rules.defs	2017-11-20 13:01:54.000000000 +0100
@@ -807,7 +807,7 @@
 ifeq (,$(filter $(distrelease),lenny etch squeeze dapper hardy jaunty karmic
lucid maverick natty oneiric))
   go_no_cpus := $(filter-out arm, $(go_no_cpus))
 endif
-go_no_systems := gnu kfreebsd-gnu
+go_no_systems := kfreebsd
 
 ifneq ($(with_base_only),yes)
   ifneq ($(separate_lang),yes)
@@ -817,7 +817,7 @@
 ifneq (,$(filter $(DEB_TARGET_ARCH_CPU),$(go_no_cpus)))
   with_go := disabled for cpu $(DEB_TARGET_ARCH_CPU)
 endif
-ifneq (,$(findstring $(DEB_TARGET_GNU_SYSTEM),$(go_no_systems)))
+ifneq (,$(findstring $(DEB_TARGET_ARCH_OS),$(go_no_systems)))
   with_go := disabled for system $(DEB_TARGET_GNU_SYSTEM)
 endif
 ifeq ($(go_no_cross)-$(DEB_CROSS),yes-yes)

Changing back to go_no_systems := kfreebsd-gnu as aurel32 did disables the build
of go also for GNU/Hurd. The culprit is to match DEB_TARGET_ARCH_OS to kfreebsd
to disable the build of go for GNU/kFreeBSD, not to match DEB_TARGET_GNU_SYSTEM
to kfreebsd-gnu, since that will match gnu too :(

rules.defs is OK for gcc-5 and gcc-6.