i2c-algo-bit: Add i2c_bit_add_numbered_bus

Add i2c_bit_add_numbered_bus(), which is equivalent to i2c_bit_add_bus
except that it calls i2c_add_numbered_adapter() at the end instead of
i2c_add_adapter().

Signed-off-by: Jean Delvare <khali@linux-fr.org>