Move android.hidl.memory@1.0-impl to system_ext

android.hidl.memory@1.0-impl is no longer installed from the latest
android version, which diverges system image into two versions. To unify
system image over target device versions, move diverging factor to the
system_ext partition.

Bug: 403049290
Test: Target with old version installs android.hidl.memory@1.0-impl in the system_ext partition
Change-Id: I6c07a6e510308781f643888fb46224a6379bb264