dmaengine: at_hdmac: Free the memset buf without holding the chan lock

stable inclusion
from stable-v5.10.155
commit 0f603bf553a70af22ced122d706feeae2bb6ed76
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7M5F4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0f603bf553a70af22ced122d706feeae2bb6ed76



--------------------------------

commit 6ba826cb upstream.

There's no need to hold the channel lock when freeing the memset buf, as
the operation has already completed. Free the memset buf without holding
the channel lock.

Fixes: 4d112426 ("dmaengine: hdmac: Add memset capabilities")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-10-tudor.ambarus@microchip.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>