samba4: Add extra useful dependencies and attempt to fix darwin build

pkgs/servers/samba/4.x-fix-ctdb-deps.patch

@@ -0,0 +1,13 @@
+diff --git a/ctdb/wscript b/ctdb/wscript
+index 3e2a992..3fe15cc 100755
+--- a/ctdb/wscript
++++ b/ctdb/wscript
+@@ -568,7 +568,7 @@ def build(bld):
+                          source='ib/ibwrapper_test.c',
+                          includes='include include/internal',
+                          deps='''replace talloc ctdb-client ctdb-common
+-                                 ctdb-system''' +
++                                 ctdb-system ctdb-common-util''' +
+                               ib_deps,
+                          install_path='${CTDB_TEST_LIBDIR}')
+ 

pkgs/servers/samba/4.x.nix

@@ -27,6 +27,11 @@
 , zlib ? null
 , ncurses ? null
 , libcap ? null
+, libunwind ? null
+, dbus ? null
+, libibverbs ? null
+, librdmacm ? null
+, systemd ? null
 }:
 
 stdenv.mkDerivation rec {
@@ -40,6 +45,7 @@ stdenv.mkDerivation rec {
   patches = [
     ./4.x-no-persistent-install.patch
     ./4.x-heimdal-compat.patch
+    ./4.x-fix-ctdb-deps.patch
   ];
 
   buildInputs = [
@@ -53,7 +59,7 @@ stdenv.mkDerivation rec {
 
     gnutls libgcrypt libgpgerror
 
-    zlib ncurses libcap
+    zlib ncurses libcap libunwind dbus libibverbs librdmacm systemd
   ];
 
   postPatch = ''