Remove the dedicated post-VMEXIT TSS reloading code now that KVM uses
VMLOAD to load host segment state, which includes TSS state.

Fixes: e79b91bb ("KVM: SVM: use vmsave/vmload for saving/restoring additional host state")
Reported-by: Venkatesh Srinivas <venkateshs@google.com>
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Link: https://lore.kernel.org/r/20230523165635.4002711-1-mizhang@google.com
[sean: massage changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>