expand_smacro: stylish nits
expand_smacro: stylish nits

- no need to split functions even if it a bit longer
  then 80 characters, it becomes hard to read it

- initialize "thead" before "tail" is more natural

- use more simple while() instead of for() with a
  long initializer

Signed-off-by: Cyrill Gorcunov <7a1ea01eee6961eb1e372e3508c2670446d086f4@gmail.com>

techkey/nasm,projedi/nasm,turingstudio/nasm,Distrotech/nasm,projedi/nasm,Distrotech/nasm,Distrotech/nasm,projedi/nasm,letolabs/nasm,techkey/nasm,letolabs/nasm,projedi/nasm,turingstudio/nasm,turingstudio/nasm,turingstudio/nasm,techkey/nasm,techkey/nasm,letolabs/nasm,Distrotech/nasm,techkey/nasm,projedi/nasm