drivers/block/z2ram: Remove TRUE/FALSE defines

Remove defines of TRUE and FALSE
  * not used in the file
  * the file is not included somewhere else

Signed-off-by: Richard Knutsson <ricknu-0@student.ltu.se>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>