ARM: SAMSUNG: Fix platform data setup for I2C adapter 0

The common static default_i2c_data structure gets bus_num set by each
s3c_i2c?_set_platdata() call, except for s3c_i2c0_set_platdata(). Thus
if for instance s3c_i2c1_set_platdata() is called prior to
s3c_i2c0_set_platdata() the I2C0 controller has bus_num set to wrong value
of 1, i.e. the one from previous set_platdata call. Fix this by also setting
bus_num for I2C0.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>