libgo: update libtool.m4 to support GNU/Hurd

This patch was incorrectly installed in the GCC repo:
https://gcc.gnu.org/pipermail/gcc-patches/2021-January/562758.html

Change-Id: I12766baf02bfdf2233f1c5bde1a270f06b020aa7
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/321076
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
diff --git a/libgo/config/libtool.m4 b/libgo/config/libtool.m4
index e744753..4ca90ee 100644
--- a/libgo/config/libtool.m4
+++ b/libgo/config/libtool.m4
@@ -2328,16 +2328,6 @@
   esac
   ;;
 
-gnu*)
-  version_type=linux
-  need_lib_prefix=no
-  need_version=no
-  library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext}${major} ${libname}${shared_ext}'
-  soname_spec='${libname}${release}${shared_ext}$major'
-  shlibpath_var=LD_LIBRARY_PATH
-  hardcode_into_libs=yes
-  ;;
-
 haiku*)
   version_type=linux
   need_lib_prefix=no
@@ -2454,7 +2444,7 @@
   ;;
 
 # This must be Linux ELF.
-linux* | k*bsd*-gnu | kopensolaris*-gnu)
+linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
   version_type=linux
   need_lib_prefix=no
   need_version=no
diff --git a/libgo/configure b/libgo/configure
index c1956d8..915eeaf 100755
--- a/libgo/configure
+++ b/libgo/configure
@@ -10739,16 +10739,6 @@
   esac
   ;;
 
-gnu*)
-  version_type=linux
-  need_lib_prefix=no
-  need_version=no
-  library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext}${major} ${libname}${shared_ext}'
-  soname_spec='${libname}${release}${shared_ext}$major'
-  shlibpath_var=LD_LIBRARY_PATH
-  hardcode_into_libs=yes
-  ;;
-
 haiku*)
   version_type=linux
   need_lib_prefix=no
@@ -10865,7 +10855,7 @@
   ;;
 
 # This must be Linux ELF.
-linux* | k*bsd*-gnu | kopensolaris*-gnu)
+linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu*)
   version_type=linux
   need_lib_prefix=no
   need_version=no
@@ -11554,7 +11544,7 @@
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11557 "configure"
+#line 11547 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11660,7 +11650,7 @@
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11663 "configure"
+#line 11653 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H