dmaengine: imx-sdma: Fix error checking in sdma_event_remap

stable inclusion
from stable-v5.10.113
commit 9bc949a181ba805b76b81d1ae1519af093328b81
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=9bc949a181ba805b76b81d1ae1519af093328b81



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[ Upstream commit 7104b9cb ]

of_parse_phandle() returns NULL on errors, rather than error
pointers. Using NULL check on grp_np to fix this.

Fixes: d078cd1b ("dmaengine: imx-sdma: Add imx6sx platform support")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Link: https://lore.kernel.org/r/20220308064952.15743-1-linmq006@gmail.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>