V4L/DVB (7260): tuner-xc3028: Don't check return code for clock reset

Only tm6000 needs to be aware when a frequency is being changed. This seems
to improve channel change detection. Other bridges don't need this.
So, better to discard any errors if this fails, and proceed changing the
channels.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>