Add OpenBMC EVB Layer README

Change-Id: Ia91ca21207f2b68e41d6a43aa280753918f461d8
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..757f3c2
--- /dev/null
+++ b/README.md
@@ -0,0 +1,10 @@
+OpenBMC Evaluation Board (EVB)
+================
+
+This is the OpenBMC Evaluation Board (EVB) layer. The boards in the EVB layer
+are for evaluation and reference. The [Board Support Package (BSP)
+layer](https://github.com/openbmc/openbmc/tree/master/meta-openbmc-bsp)
+should be used to support a hardware device in a system. Therefore, there
+should not be any EVB layers in a system's bblayers.conf, the BSP layer should
+be used instead. Boards might be found be in both the EVB layer and the BSP
+layer.