- remove spurious spaces and tabs at end of lines
    - make sure if, while, for, switch has a space before the opening '('
    - make sure no line has more than 80 chars
    - move initializations to the declaration line where possible
    - bitwise, logical and arithmetic operators have spaces before and after,
      improving readability of complex expressions
    - remove uneeded () in returns
    - other minor cleanups

Before:
   text    data     bss     dec     hex filename
  15228   12376    2560   30164    75d4 net/core/dev.o
After:
   text    data     bss     dec     hex filename
  14840   12364    2624   29828    7484 net/core/dev.o