path: remove unused header

The "environment.h" header is included in "path.c", but none of the
functions or macros it provides are used in this file.

Signed-off-by: K Jayatheerth <jayatheerthkulkarni2005@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

path.c

@@ -4,7 +4,6 @@
 
 #include "git-compat-util.h"
 #include "abspath.h"
-#include "environment.h"
 #include "gettext.h"
 #include "repository.h"
 #include "strbuf.h"