phosphor-settings-read-settings-mrw recipe

phosphor-settings-read-settings-mrw recipe calls gen_settings.pl
to replace any MRW variables in mrw-override-settings.yaml with
their MRW value.
The file generated by gen_settings.pl, mrw-settings.override.yaml,
is then used as an override of phosphor-settings.

mrw-override-settings.yaml by default is empty so no settings are
actually overwritten. A later commit will modify
mrw-override-settings.yaml in the Witherspoon layer.

Change-Id: I3134dbb834ff52abe5be589dd1d88444b8577254
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/common/recipes-phosphor/settings/phosphor-settings-read-settings-mrw/mrw-override-settings.yaml b/common/recipes-phosphor/settings/phosphor-settings-read-settings-mrw/mrw-override-settings.yaml
new file mode 100644
index 0000000..c0fbede
--- /dev/null
+++ b/common/recipes-phosphor/settings/phosphor-settings-read-settings-mrw/mrw-override-settings.yaml
@@ -0,0 +1,3 @@
+# Default MRW settings override definition YAML - empty.
+# Any MRW variables, marked by MRW_<MRW variable name>, are replaced with their
+# MRW value.