Fix #34908: compressed DDS files did not display properly when their mipmap levels
did not go down to 1x1 image size, need to set GL_TEXTURE_MAX_LEVEL then.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@55906 954f8c5b-7b00-dc11-b283-0030488c597c