V4L/DVB (6212): pvrusb2: I2C adapter tweaks from Jean Delvare

* I2C adapters aren't expected to handle I2C_M_NOSTART unless they
  really have to. As the pvrusb2 driver doesn't support it, I take it
  that it doesn't need it so it shouldn't mention it at all.
* I2C_FUNC_SMBUS_EMUL includes I2C_FUNC_SMBUS_BYTE_DATA so listing
  both is redundant.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>