http-push, http-walker: style fixes

http-push, http-walker: style fixes

- Use tabs to indent, instead of spaces.

- Do not use curly-braces around a single statement body in
  if/while statement;

- Do not start multi-line comment with description on the first
  line after "/*", i.e.

  /*
   * We prefer this over...
   */

  /* comments like
   * this (notice the first line)
   */

Signed-off-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>