dmaengine: idxd: add RO check for wq max_batch_size write

stable inclusion
from stable-v5.10.113
commit 9a3c026dc3a59fa23c63d90752f07538a3c75646
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9a3c026dc3a59fa23c63d90752f07538a3c75646



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[ Upstream commit 66903461 ]

Block wq_max_batch_size_store() when the device is configured as read-only
and not configurable.

Fixes: e7184b15 ("dmaengine: idxd: add support for configurable max wq batch size")
Reported-by: Bernice Zhang <bernice.zhang@intel.com>
Tested-by: Bernice Zhang <bernice.zhang@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/164971493551.2201159.1942042593642155209.stgit@djiang5-desk3.ch.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>