arb_texture_buffer_object: Test clamping of texture buffer's size

Tests that texture buffer's size cannot exceed GL_MAX_TEXTURE_BUFFER_SIZE_ARB even if underlying buffer allows it to be bigger. In other words the size of texture buffer must be clamped to the GL_MAX_TEXTURE_BUFFER_SIZE_ARB by the driver.

Issue: https://gitlab.freedesktop.org/mesa/mesa/issues/1723

Signed-off-by: Dmytro Nester <dmytro.nester@globallogic.com>