ANDROID: KVM: arm64: Consolidate allowed and restricted guest cpu feature checks

The definitions for allowed and restricted cpu features for
protected guests, which are based on feature registers were
defined and checked for separately. This resulted in an
inconsistency when checking if pointer authentication is allowed,
which resulted in trapping it for protected guests despite it
being allowed.

To avoid this happening in the future, consolidate the
definitions into one. Use that new definition to construct the
guest view of the feature registers for consistency.

Bug: 278749606
Change-Id: Ia290b98a44ca533578add5ab4ca06888eb62e507
Fixes: 6c30bfb1 ("KVM: arm64: Add handlers for protected VM System Registers")
Reported-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>