Indent libswscale:

- Use 4 spaces throughout for indentation;
- Fix inconsistent indentation;
- Indent function calls and declarations aligning arguments on multiple lines
  to the column after the opening parentheses;
- Align asm code to the column 4 spaces after the call to __asm__();
- Align cases in switch statements to the same column as "switch".

Originally committed as revision 29522 to svn://svn.mplayerhq.hu/mplayer/trunk/libswscale