clk: en7523: fix wrong pointer check in en7523_clk_probe()

Check the real return value of devm_platform_ioremap_resource()
in en7523_clk_probe().

Fixes: 1e627317 ("clk: en7523: Add clock driver for Airoha EN7523 SoC")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220426131539.388382-1-yangyingliang@huawei.com


Acked-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>