iommu/amd: Make amd_iommu_apply_ivrs_quirks() static inline

At least the version in the header file to fix a compile warning about
the function being unused.

Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200630124611.23153-1-joro@8bytes.org