i2c: tiny-usb: check usb base class before assuming the interface on device is for...

i2c: tiny-usb: check usb base class before assuming the interface on device is for this driver

Patch allows usb devices with multiple interfaces to use this driver without
this driver assuming all interfaces are i2c-tiny-usb.

Signed-off-by: Harry Geyer <harry.geyer@devtank.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230727162255.21551-1-harry.geyer@devtank.co.uk
Signed-off-by: Wolfram Sang <wsa@kernel.org>