Fix all warnings/errors on Blackberry.

Revert GLES3 headers as they didn't include nvidia extensions.

base/BlackberryDisplay.cpp

@@ -5,7 +5,7 @@
 // Blackberry implementation of the framework.
 #include "BlackberryMain.h"
 
-char* BlackberryMain::displayTypeString(int type)
+const char* BlackberryMain::displayTypeString(int type)
 {
 	switch (type)
 	{

base/BlackberryMain.h

@@ -64,7 +64,7 @@ private:
 
 	void  handleInput(screen_event_t screen_event);
 
-	char* displayTypeString(int type);
+	const char* displayTypeString(int type);
 	void  startDisplays();
 	void* startDisplay(int idx);
 	void  realiseDisplay(int idx);

gfx/gl_common.h

@@ -3,9 +3,6 @@
 #ifdef IOS
 #include <OpenGLES/ES3/gl.h>
 #include <OpenGLES/ES3/glext.h>
-#elif defined(BLACKBERRY)
-#include <GLES3/gl3.h>
-#include <GLES3/gl3ext.h>
 #elif defined(USING_GLES2)
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>