Rename package name of IPv6ProvisioningLossQuirkParcelable.

Move new added IPv6ProvisioningLossQuirkParcelable.aidl to new
directory android/net/networkstack/aidl, also change the package
name to clearly identify AIDL classes.

Also lengthen the variable name inside NetworkAttributesParcelable
to ipv6ProvisioningLossQuirk.

Bug: 157534516
Test: atest NetworkStackTests
Change-Id: Ie2e0eb8078244a469a95ddeab6a933290ae1bcb3