arm64: Add ARM64_HYP_OFFSET_LOW capability

As we need to indicate to the rest of the kernel which region of
the HYP VA space is safe to use, add a capability that will
indicate that KVM should use the [VA_BITS-2:0] range.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

arch/arm64/include/asm/cpufeature.h

@@ -36,8 +36,9 @@
 #define ARM64_HAS_VIRT_HOST_EXTN		11
 #define ARM64_WORKAROUND_CAVIUM_27456		12
 #define ARM64_HAS_32BIT_EL0			13
+#define ARM64_HYP_OFFSET_LOW			14
 
-#define ARM64_NCAPS				14
+#define ARM64_NCAPS				15
 
 #ifndef __ASSEMBLY__