glcontext: initialize {major,minor}_version variables
glcontext: initialize {major,minor}_version variables

If the underlying context does not support querying the OpenGL version
using GL_MAJOR, GL_MINOR, major_version and minor_version are left
uninitialized but are still used to determine the OpenGL version.

gopro/gopro-lib-node.gl,gopro/gopro-lib-node.gl,gopro/gopro-lib-node.gl,gopro/gopro-lib-node.gl