KVM: arm/arm64: Documentation: Update arm-vgic-v3.txt

Update error code returned for Invalid CPU interface register
value and access in AArch32 mode.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Documentation/virtual/kvm/devices/arm-vgic-v3.txt

@@ -118,7 +118,7 @@ Groups:
     -EBUSY: One or more VCPUs are running
 
 
-  KVM_DEV_ARM_VGIC_CPU_SYSREGS
+  KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS
   Attributes:
     The attr field of kvm_device_attr encodes two values:
     bits:     | 63      ....       32 | 31  ....  16 | 15  ....  0 |
@@ -139,13 +139,15 @@ Groups:
     All system regs accessed through this API are (rw, 64-bit) and
     kvm_device_attr.addr points to a __u64 value.
 
-    KVM_DEV_ARM_VGIC_CPU_SYSREGS accesses the CPU interface registers for the
+    KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS accesses the CPU interface registers for the
     CPU specified by the mpidr field.
 
+    CPU interface registers access is not implemented for AArch32 mode.
+    Error -ENXIO is returned when accessed in AArch32 mode.
   Errors:
     -ENXIO: Getting or setting this register is not yet supported
     -EBUSY: VCPU is running
-    -EINVAL: Invalid mpidr supplied
+    -EINVAL: Invalid mpidr or register value supplied
 
 
   KVM_DEV_ARM_VGIC_GRP_NR_IRQS
@@ -204,3 +206,6 @@ Groups:
     architecture defined MPIDR, and the field is encoded as follows:
       | 63 .... 56 | 55 .... 48 | 47 .... 40 | 39 .... 32 |
       |    Aff3    |    Aff2    |    Aff1    |    Aff0    |
+  Errors:
+    -EINVAL: vINTID is not multiple of 32 or
+     info field is not VGIC_LEVEL_INFO_LINE_LEVEL