egl: Add OpenGL_ES to API string regardless of GLES version

egl: Add OpenGL_ES to API string regardless of GLES version

According to the EGL specifications eglQueryString(EGL_CLIENT_APIS)
should return a string containing a combination of "OpenGL", "OpenGL_ES"
and "OpenVG", any other values would be considered invalid. Due to this
when the API string is constructed, the version of GLES should be
disregarded and "OpenGL_ES" should be attached once instead of
"OpenGL_ES2" and "OpenGL_ES3".

Fixes:
dEQP-EGL.functional.negative_api* and
dEQP-EGL.functional.query_context.simple.query_api

Signed-off-by: Plamena Manolova <plamena.manolova@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>