mtd: OneNAND: Introduce chip_probe function

Samsung SoCs use the own OneNAND controler and detect OneNAND chip at power on.
To use this feature, introduce the chip_probe function.

Also remove workaround for Samsung SoCs.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>