[T-Only] Add android.hardware.power-V3-ndk to VndkMustUseVendorVariantList

8550 uses the AIDL V3 PowerHAL. Qualcomm must be disabling
build restrictions because the below error occurs in
LA.QSSI.13.0.r1.

FAILED: out/target/product/spes/obj/SHARED_LIBRARIES/android.hardware.power-V3-ndk.vendor_intermediates/same_vndk_variants.timestamp
/bin/bash -c "(CLANG_BIN=\"prebuilts/clang/host/linux-x86/clang-r450784d/bin\" CROSS_COMPILE=\"prebuilts/clang/host/linux-x86/clang-r450784d/bin/llvm-\" XZ=\">ERROR: VNDK library android.hardware.power-V3-ndk has different core and vendor variants! This means that the copy used in the system.img/etc and vendor.img/e>
ERROR: 1). Remove differences, possibly using the libvndksupport function android_is_in_vendor_process in order to turn this into a runtime difference.
ERROR: 2). Add the library to the VndkMustUseVendorVariantList variable in build/soong/cc/config/vndk.go, which is used to acknowledge this difference.

This is expected because vendor versions of AIDL are by
default different from core versions per
https://android.googlesource.com/platform/build/soong/+/43b2c668da97601f828c7a42001147181a83449e%5E%21/#F0

There are a number of commits in AOSP master that will
prevent this compilation error, however, to minimize
risk on T, we will match the V2 and V1 behavior.

Change-Id: If47fed934a8d26ac9515012a02dd188c88ca18b2