GL_NONE is primarily a renderbuffer format, and GL_NO_ERROR more
clearly conveys the meaning when used as a validation return code.
Also, GL_NONE is not defined in OpenGL ES 1.1 (but GL_NONE_OES is,
as a renderbuffer format).

Change-Id: Ie1c00009c30c8d2717de15c7e27db295ecd9de1e
Reviewed-on: https://swiftshader-review.googlesource.com/17489Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>