bmc-ready: include new error codes in interfaces

This will generate the appropriate bindings and ensure the error is
passed back to the caller allowing them to properly handle this type of
error.

Change-Id: I63301d0371d27835417fcba503c32f854f1919bd
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/yaml/xyz/openbmc_project/State/Chassis.interface.yaml b/yaml/xyz/openbmc_project/State/Chassis.interface.yaml
index 7c74a04..13606a2 100644
--- a/yaml/xyz/openbmc_project/State/Chassis.interface.yaml
+++ b/yaml/xyz/openbmc_project/State/Chassis.interface.yaml
@@ -7,6 +7,8 @@
       description: >
           The desired power transition to start on this chassis. This will be
           preserved across AC power cycles of the BMC.
+      errors:
+          - xyz.openbmc_project.State.Chassis.Error.BMCNotReady
 
     - name: CurrentPowerState
       type: enum[self.PowerState]