fix misplaced quotes in kmod-preamble

rpm/redhat/zfs-kmod.spec.in has a typo in the shell code that
creates the kmod-preamble file.  This typo results in the
preamble file having the wrong name,

./SOURCES/kmod-preamblenObsoletes

and missing the Obsoletes clause that has become part of the name.

Because the filename is incorrect, the built package does not have
"obsoletes" or "conflicts" set.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes openzfs#11851

rpm/redhat/zfs-kmod.spec.in

@@ -17,8 +17,8 @@ BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 # by generating a preamble text file which kmodtool can append to the spec file.
 %(/bin/echo -e "\
 Requires:       @PACKAGE@ = %{version}\n\
-Conflicts:      @PACKAGE@-dkms\n\n" > %{_sourcedir}/kmod-preamble\n\
-Obsoletes:      spl-kmod)
+Conflicts:      @PACKAGE@-dkms\n\
+Obsoletes:      spl-kmod\n\n" > %{_sourcedir}/kmod-preamble)
 
 # LDFLAGS are not sanitized by arch/*/Makefile for these architectures.
 %ifarch ppc ppc64 ppc64le aarch64