glx: Store the RENDER_TYPE in indirect rendering

v2 (idr): Open-code the check for GLX_RENDER_TYPE.
dri2_convert_glx_attribs can't be called from here because that function
only exists in direct-rendering builds.  Also add a stub version of
indirect_create_context_attribs to tests/fake_glx_screen.cpp to prevent
'make check' regressions.

Signed-off-by: Tomasz Lis <tomasz.lis@intel.com>
Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

src/glx/create_context.c

@@ -84,7 +84,9 @@ glXCreateContextAttribsARB(Display *dpy, GLXFBConfig config,
 #ifdef GLX_USE_APPLEGL
       gc = applegl_create_context(psc, cfg, share, 0);
 #else
-      gc = indirect_create_context(psc, cfg, share, 0);
+      gc = indirect_create_context_attribs(psc, cfg, share, num_attribs,
+              (const uint32_t *) attrib_list,
+              &dummy_err);
 #endif
    }