Yocto 2.3

Move OpenBMC to Yocto 2.3(pyro).

Tested: Built and verified Witherspoon and Palmetto images
Change-Id: I50744030e771f4850afc2a93a10d3507e76d36bc
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
Resolves: openbmc/openbmc#2461
diff --git a/import-layers/yocto-poky/meta/classes/relative_symlinks.bbclass b/import-layers/yocto-poky/meta/classes/relative_symlinks.bbclass
new file mode 100644
index 0000000..3157737
--- /dev/null
+++ b/import-layers/yocto-poky/meta/classes/relative_symlinks.bbclass
@@ -0,0 +1,5 @@
+do_install[postfuncs] += "install_relative_symlinks"
+
+python install_relative_symlinks () {
+    oe.path.replace_absolute_symlinks(d.getVar('D'), d)
+}