platform/x86: apple-gmux: use resource_size() with res

stable inclusion
from stable-v5.10.90
commit 7da855e93964893d48df8ad60fc30a8ac8327506
bugzilla: 186168 https://gitee.com/openeuler/kernel/issues/I4SHY1

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7da855e93964893d48df8ad60fc30a8ac8327506



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[ Upstream commit eb66fb03 ]

This should be (res->end - res->start + 1) here actually,
use resource_size() derectly.

Signed-off-by: Wang Qing <wangqing@vivo.com>
Link: https://lore.kernel.org/r/1639484316-75873-1-git-send-email-wangqing@vivo.com


Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>