malidp: Fix NULL vs IS_ERR() checking

stable inclusion
from stable-v5.19.17
commit 15342f93
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6IXPT
CVE: CVE-2023-23004

Reference: https://github.com/torvalds/linux/commit/15342f930ebebcfe36f2415049736a77d7d2e045



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commit 15342f93 upstream.

The get_sg_table() function does not return NULL.
It returns error pointers.

Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://lore.kernel.org/dri-devel/20211213072115.18098-1-linmq006@gmail.com/


Signed-off-by: Lipeng Sang <sanglipeng1@jd.com>