Merge: drm/vmwgfx: Fix guests running with TDX/SEV

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-10/-/merge_requests/1320

JIRA: https://issues.redhat.com/browse/RHEL-101642

Commit 81256a5 ("x86/mm: Make memremap(MEMREMAP_WB) map memory as
encrypted by default") changed the default behavior of
memremap(MEMREMAP_WB) and started mapping memory as encrypted.
The driver requires the fifo memory to be decrypted to communicate with
the host but was relaying on the old default behavior of
memremap(MEMREMAP_WB) and thus broke.

Fix it by explicitly specifying the desired behavior and passing
MEMREMAP_DEC to memremap.

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>

Approved-by: Mika Penttilä <mpenttil@redhat.com>
Approved-by: José Expósito <jexposit@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: CKI GitLab Kmaint Pipeline Bot <26919896-cki-kmaint-pipeline-bot@users.noreply.gitlab.com>

Author: CKI KWF Bot

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

@@ -769,7 +769,7 @@ static int vmw_setup_pci_resources(struct vmw_private *dev,
 		dev->fifo_mem = devm_memremap(dev->drm.dev,
 					      fifo_start,
 					      fifo_size,
-					      MEMREMAP_WB);
+					      MEMREMAP_WB | MEMREMAP_DEC);
 
 		if (IS_ERR(dev->fifo_mem)) {
 			drm_err(&dev->drm,