sparc64: bypass iommu to use 64bit address space

sparc64: bypass iommu to use 64bit address space

This patch is internal only not for UPSTREAM. This is a temporary
workaround based on UEK2 commit c1a12ed1d125
("sparc64: enable iommu bypass workaround for IB. This is temporary.")

Current design of sparc iommu is based on iommu V1 APIs which at max
can have 2G/8K DMA addresses. Due to this, kernel entity (e.g. i40e,
PSIF) requesting more than 2G/8K DMA addresses does not work at all.
This patch adds temporary workaround to remedy this issue by bypassing
iommu.

When 64bit iommu implementation is complete, this workaround will be
reverted.

Orabug: 21149316
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
(cherry picked from commit d751c5e1e6575b1dc119383045ba488e0d30de4d)
(cherry picked from commit 2ecc8426003036609fc447c3cf2dcf54139770cf)