glretrace: Fix handling of WGL/GLX_EXT_create_context_{es,es2}_profile

WGL/GLX_EXT_create_context_es2_profile came first.
WGL/GLX_EXT_create_context_es_profile came second.

As spotted by Chad Versace in
https://github.com/waffle-gl/waffle/issues/23#issuecomment-63392911
specs: Fix GL_PURGEABLE_APPLE type.