hwc: Rename libexternal to serve HDMI as primary or external

This change will make is easier to build new functionality
applicable to both HDMI scenarios.

Change-Id: I417184568cb65a49c2ccb4199aff313ae2ee9b24
diff --git a/libhwcomposer/hwc.cpp b/libhwcomposer/hwc.cpp
index ae1389d..288b2e0 100644
--- a/libhwcomposer/hwc.cpp
+++ b/libhwcomposer/hwc.cpp
@@ -34,7 +34,7 @@
 #include "hwc_fbupdate.h"
 #include "hwc_mdpcomp.h"
 #include "hwc_dump_layers.h"
-#include "external.h"
+#include "hdmi.h"
 #include "hwc_copybit.h"
 #include "hwc_ad.h"
 #include "profiler.h"
@@ -442,7 +442,7 @@
         if(mode == HWC_POWER_MODE_NORMAL) {
             // Enable HPD here, as during bootup POWER_MODE_NORMAL is set
             // when SF is completely initialized
-            ctx->mExtDisplay->setHPD(1);
+            ctx->mHDMIDisplay->setHPD(1);
         }
 
         ctx->dpyAttr[dpy].isActive = not(mode == HWC_POWER_MODE_OFF);