If your BIOS is broken like reported there is nothing we can do.
From googling it seems DMAR is used for IOMMU/GPU-passthrough something you are likely not using. Seems like you can safely ignore this.
EDIT:
The laptop is old. The vendor is highly unlikely to ever try address this issue.
For clarity GPU passthrough would require your laptop have multiple GPU's as the guest OS in the VM would take exclusive control of the GPU. It appears your laptop has integrated graphics only so you could never use passthrough anyway.
