[media] dvb_frontend: fix a regression with DVB-S zig-zag
[media] dvb_frontend: fix a regression with DVB-S zig-zag

Changeset 5bfaadde broke zig-zag for DVB-S drivers that don't
implement get_tune_settings() callback.

Fix the code, in order to allow it to work as before, otherwise
some channels may not be tuned anymore.

Fix Fedora Bugzilla:
	https://bugzilla.redhat.com/show_bug.cgi?id=814404

Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@kernel.org # for Kernel v3.3
Reported-by: Michael Heijenga <2cf1d67b4a73f3d9c2e444007740a56681a102ca@googlemail.com>
Tested-by: Michael Heijenga <2cf1d67b4a73f3d9c2e444007740a56681a102ca@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <ad86ba2154032c9f55743a190faa2459a9d61d42@redhat.com>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas