sw64: radeon: add a force flush to delay work when radeon uvd suspend

Sunway inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I56XI1



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On sw64 platform, system suspend operation may occur Dfault error during
that video player is running at the same time, so let's fix it by adding
a force flush.

Signed-off-by: Xu Chenjiao <xuchenjiao@wxiat.com>

Signed-off-by: Gu Zitao <guzitao@wxiat.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>