Refactor: rename namespace witherspoon to phosphor

This repo now becomes phosphor-power, rename namespace witherspoon to
phosphor to make it generic.

Signed-off-by: Lei YU <mine260309@gmail.com>
Change-Id: Icb9f8a7c33065add99f2bf42ed55745a28fa0424
diff --git a/power-sequencer/templates/ucd90160_defs.mako.cpp b/power-sequencer/templates/ucd90160_defs.mako.cpp
index 1775158..c7a2db6 100644
--- a/power-sequencer/templates/ucd90160_defs.mako.cpp
+++ b/power-sequencer/templates/ucd90160_defs.mako.cpp
@@ -2,7 +2,7 @@
 
 #include "ucd90160.hpp"
 
-namespace witherspoon
+namespace phosphor
 {
 namespace power
 {
@@ -56,4 +56,4 @@
 };
 
 } // namespace power
-} // namespace witherspoon
+} // namespace phosphor