drm/msm: Fix null pointer dereferences without iommu
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.18.3 by commit f09937e80f9bc792965476c9a528f26c8fdc9179, it was introduced in version v5.18 by commit bc2112583a0b473f5c4ba87c00da84abd5d0b3fd. For more details please see the references link.