glew: build for EGL in non-X11 distros

glew: build for EGL in non-X11 distros

The glew 2.0.0 release added support for building for EGL:

  http://glew.sourceforge.net/log.html

Add PACKAGECONFIG options for 'opengl' (ie the previous default, with
dependencies on opengl and X11) and 'egl-gles2', which depends on EGL
and GLESv2 and allow glew to be built for non-X11 distros.

(From OE-Core rev: f6344f20e3aed640b3218438e69c0b641e58d630)

Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>