mesa: Rename API_OPENGL to API_OPENGL_COMPAT.

This should help avoid confusion now that we're using the gl_api enum
to distinguishing between core and compatibility API's.  The
corresponding enum value for core API's is API_OPENGL_CORE.

Acked-by: Eric Anholt <eric@anholt.net>
Acked-by: Matt Turner <mattst88@gmail.com>
Acked-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/main/context.c

@@ -963,7 +963,7 @@ _mesa_initialize_context(struct gl_context *ctx,
 	  sizeof(ctx->TextureFormatSupported));
 
    switch (ctx->API) {
-   case API_OPENGL:
+   case API_OPENGL_COMPAT:
       ctx->Save = _mesa_create_save_table(ctx);
       if (!ctx->Save) {
          _mesa_reference_shared_state(ctx, &ctx->Shared, NULL);