KVM: arm64: Move hyp-init.S to nVHE

hyp-init.S contains the identity mapped initialisation code for the
non-VHE code that runs at EL2. It is only used for non-VHE.

Adjust code that calls into this to use the prefixed symbol name.

Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-8-dbrazdil@google.com