Move FVP power driver to FVP platform

Move the FVP power driver to a directory under the FVP platform
port as this is not a generically usable driver.

Change-Id: Ibc78bd88752eb3e3964336741488349ac345f4f0
diff --git a/plat/fvp/bl31_plat_setup.c b/plat/fvp/bl31_plat_setup.c
index 9bf83eb..bd167df 100644
--- a/plat/fvp/bl31_plat_setup.c
+++ b/plat/fvp/bl31_plat_setup.c
@@ -30,8 +30,8 @@
 
 #include <platform.h>
 #include <arch.h>
-#include <fvp_pwrc.h>
 #include <console.h>
+#include "drivers/pwrc/fvp_pwrc.h"
 
 /*******************************************************************************
  * Declarations of linker defined symbols which will help us find the layout