Add virtual/phosphor-logging-callouts

This virtual generates mappings between sysfs device paths and inventory
items.

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

Resolves openbmc/openbmc#1093
Resolves openbmc/openbmc#1249

Change-Id: If67b4ef0850910a076ca212197a4bd0e704d0266
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/classes/phosphor-logging.bbclass b/classes/phosphor-logging.bbclass
new file mode 100644
index 0000000..18f53d4
--- /dev/null
+++ b/classes/phosphor-logging.bbclass
@@ -0,0 +1 @@
+callouts_datadir="${datadir}/phosphor-logging/callouts"