Provide the phosphor-fan-presence config YAML

On MRW based systems, this YAML will be generated from the
MRW XML, otherwise the example YAML provided by the
phosphor-fan-presence repository will be used in the build.

Change-Id: I1bf914a7e26067f62f2b2bf8b7ba1ba43591c5dc
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/meta-phosphor/classes/phosphor-fan-presence.bbclass b/meta-phosphor/classes/phosphor-fan-presence.bbclass
new file mode 100644
index 0000000..b59f1f5
--- /dev/null
+++ b/meta-phosphor/classes/phosphor-fan-presence.bbclass
@@ -0,0 +1 @@
+presence_datadir="${datadir}/phosphor-fan-presence"