[media] radio-sf16fmr2: fix session mismatches

WARNING: drivers/media/radio/built-in.o(.data+0x284): Section mismatch in reference from the variable fmr2_driver to the function .init.text:fmr2_probe()
The variable fmr2_driver references
the function __init fmr2_probe()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

WARNING: drivers/media/built-in.o(.data+0x48200): Section mismatch in reference from the variable fmr2_driver to the function .init.text:fmr2_probe()
The variable fmr2_driver references
the function __init fmr2_probe()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>