arm64: Simplify init_el2_state to be non-VHE only

As init_el2_state is now nVHE only, let's simplify it and drop
the VHE setup.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: David Brazdil <dbrazdil@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210208095732.3267263-9-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>