FLAT objects cannot have multiple sections, so using the L1 attributes breaks

linking. The FDPIC relocs also break for any other format. Thus check the
compiler environment and select the appropriate sections/relocs.
patch by Mike Frysinger, vapier.adi a gmail d com

Originally committed as revision 26010 to svn://svn.mplayerhq.hu/mplayer/trunk/libswscale