ANDROID: KVM: arm64: iommu: Fix power tracking

While reworking power flow for Android16, one line of code
remained which is not correct.

power state on suspend should only be updated on success, similar
to resume.

Bug: 357781595
Change-Id: Ib894362085eaa6f123b0d9083f430ad8a7c14569
Signed-off-by: Mostafa Saleh <smostafa@google.com>