ARM/ARM64: KVM: Emulate PSCI v0.2 MIGRATE_INFO_TYPE and related functions

This patch adds emulation of PSCI v0.2 MIGRATE, MIGRATE_INFO_TYPE, and
MIGRATE_INFO_UP_CPU function calls for KVM ARM/ARM64.

KVM ARM/ARM64 being a hypervisor (and not a Trusted OS), we cannot provide
this functions hence we emulate these functions in following way:
1. MIGRATE - Returns "Not Supported"
2. MIGRATE_INFO_TYPE - Return 2 i.e. Trusted OS is not present
3. MIGRATE_INFO_UP_CPU - Returns "Not Supported"

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>