V4L/DVB (12699): cx18: ir-kbd-i2c initialization data should point to a persistent object

ir-kbd-i2c's ir_probe() function can be called much later (i.e. at ir-kbd-i2c
module load), than the lifetime of a struct IR_i2c_init_data allocated off of
the stack in cx18_i2c_new_ir() at registration time.  Make sure we pass
a pointer to a persistent IR_i2c_init_data object at i2c registration time.

Thanks to Brian Rogers for pointing out a solution, and Dustin Mitchell for
testing against a 2.6.30 kernel.

Reported-by: Dustin Mitchell <soxslayer@gmail.com>
Reported-by: Brian Rogers <brian@xyzw.org>
Tested-by: Dustin Mitchell <soxslayer@gmail.com>
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>