mtd: rawnand: fsmc: handle clk prepare error in fsmc_nand_resume()

In fsmc_nand_resume(), the return value of clk_prepare_enable() should be
checked since it might fail.

Fixes: e25da1c0

 ("mtd: fsmc_nand: Add clk_{un}prepare() support")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20230817115839.10192-1-yiyang13@huawei.com