Persist current mode property framework

Add the ability to save the current  mode property value to
persisted storage.

Change-Id: I354fce7c11a61871a49c9b205dc79ee598f8b1c8
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
diff --git a/configure.ac b/configure.ac
index 8ffda9b..0421801 100644
--- a/configure.ac
+++ b/configure.ac
@@ -109,6 +109,12 @@
        AC_DEFINE_UNQUOTED([CONTROL_OBJPATH], ["$CONTROL_OBJPATH"],
                           [The fan control root object path])
 
+       AC_ARG_VAR(CONTROL_PERSIST_ROOT_PATH, [Root path for persisting zone property states])
+       AS_IF([test "x$CONTROL_PERSIST_ROOT_PATH" == "x"],
+             [CONTROL_PERSIST_ROOT_PATH="/var/lib/phosphor-fan-presence/control"])
+       AC_DEFINE_UNQUOTED([CONTROL_PERSIST_ROOT_PATH], ["$CONTROL_PERSIST_ROOT_PATH"],
+                          [Root path for persisting zone property states])
+
        # Add optional yaml file arguments
        AC_ARG_VAR(FAN_DEF_YAML_FILE,
                   [The fan definition file to use])