Fan control: Create Zone class

This class represents a fan zone, which is a collection
of fans that are always set to a speed together.

Change-Id: I5646f07b7b136aad216dabded3b5da3e9da0a531
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/control/Makefile.am b/control/Makefile.am
index 56ba948..fc2a2dc 100644
--- a/control/Makefile.am
+++ b/control/Makefile.am
@@ -8,7 +8,8 @@
 	generated.cpp \
 	fan.cpp \
 	main.cpp \
-	manager.cpp
+	manager.cpp \
+	zone.cpp
 
 phosphor_fan_control_LDADD = \
 	$(top_builddir)/libfan.la \