string-list: rename the include guard to STRING_LIST_H
string-list: rename the include guard to STRING_LIST_H

Signed-off-by: Thiago Farina <2a0e9cb90b21b2938e0b17d56218ee872370e237@gmail.com>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git