native frameworks: 64-bit compile issues

- Fix format (print/scanf)
- Suppress unused argument warning messages (bonus)

Change-Id: I05c7724d2aba6da1e82a86000e11f3a8fef4e728
diff --git a/opengl/libagl/state.cpp b/opengl/libagl/state.cpp
index 4bc653a..1d5def5 100644
--- a/opengl/libagl/state.cpp
+++ b/opengl/libagl/state.cpp
@@ -219,11 +219,11 @@
 #endif
 
 // These ones are super-easy, we're not supporting those features!
-void glSampleCoverage(GLclampf value, GLboolean invert) {
+void glSampleCoverage(GLclampf /*value*/, GLboolean /*invert*/) {
 }
-void glSampleCoveragex(GLclampx value, GLboolean invert) {
+void glSampleCoveragex(GLclampx /*value*/, GLboolean /*invert*/) {
 }
-void glStencilFunc(GLenum func, GLint ref, GLuint mask) {
+void glStencilFunc(GLenum func, GLint /*ref*/, GLuint /*mask*/) {
     ogles_context_t* c = ogles_context_t::get();
     if (func < GL_NEVER || func > GL_ALWAYS) {
         ogles_error(c, GL_INVALID_ENUM);