path.h: make REPO_GIT_PATH_FUNC repository agnostic

git_pathdup uses the_repository internally, but the macro
REPO_GIT_PATH_FUNC is specifically made for arbitrary repositories.
Switch to repo_git_path which works on arbitrary repositories.

Signed-off-by: Stefan Beller <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: stefanbeller

path.h

@@ -165,7 +165,7 @@ extern void report_linked_checkout_garbage(void);
 	const char *git_path_##var(struct repository *r) \
 	{ \
 		if (!r->cached_paths.var) \
-			r->cached_paths.var = git_pathdup(filename); \
+			r->cached_paths.var = repo_git_path(r, filename); \
 		return r->cached_paths.var; \
 	}