Add virtual/phosphor-ipmi-sensor-inventory

This virtual provides a YAML file that serves as sensor
inventory configuration for phosphor-host-ipmid.

Add a native recipe that builds the configuration from MRW.
Set this recipe as the default for OpenPOWER systems.

Resolves openbmc/openbmc#781
Resolves openbmc/openbmc#1212

Change-Id: I25034dd3ed825e2ef320ab0b38ac2f733afded47
Signed-off-by: Ratan Gupta <ratagupt@in.ibm.com>
diff --git a/classes/phosphor-ipmi-host.bbclass b/classes/phosphor-ipmi-host.bbclass
new file mode 100644
index 0000000..2857029
--- /dev/null
+++ b/classes/phosphor-ipmi-host.bbclass
@@ -0,0 +1 @@
+sensor_datadir="${datadir}/phosphor-ipmi-host/sensor"