arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardening

arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardening

The function SMCCC_ARCH_WORKAROUND_1 was introduced as part of SMC
V1.1 Calling Convention to mitigate CVE-2017-5715. This patch uses
the standard call SMCCC_ARCH_WORKAROUND_1 for Falkor chips instead
of Silicon provider service ID 0xC2001700.

Cc: <[email protected]> # 4.14+
Signed-off-by: Shanker Donthineni <[email protected]>
[maz: reworked errata framework integration]
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Will Deacon <[email protected]>