kmod-zfs should obsolete kmod-spl as well as spl-kmod

Without this Obsoletes, using packages built --with-spec=redhat, an
upgrade from zfs-0.7 to zfs-2.x does not cause the kmod-spl-0.7 package
to be removed.

Signed-off-by: Olaf Faaland <faaland1@llnl.gov>

rpm/redhat/zfs-kmod.spec.in

@@ -18,6 +18,7 @@ BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 %(/bin/echo -e "\
 Requires:       @PACKAGE@ = %{version}\n\
 Conflicts:      @PACKAGE@-dkms\n\
+Obsoletes:      kmod-spl\n\
 Obsoletes:      spl-kmod\n\n" > %{_sourcedir}/kmod-preamble)
 
 # LDFLAGS are not sanitized by arch/*/Makefile for these architectures.