mtd: onenand: samsung: use devm_ function to simplify code and fix some leaks

Convert all error handling code in 's3c_onenand_probe()' to
resource-managed alternatives in order to simplify code.

This fixes a resource leak if 'platform_get_resource()' fails at line 872.

The 'request_irq()' at line 971 was also un-balanced. It is now
resource-managed.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>