Mostly whitespace cleanups and style(9) fixes focused on "if(" -> "if ("

    Change some nearby memset()s to bzero()s or to calloc allocations to
    take advantage of M_ZERO). Reverse some error tests to reduce high
    levels of indentation. Move the sg_cleanup() call out of the maplist
    loop in DRM(takedown)-- I can't see any need for it to be inside.