repository: remove unnecessary include of path.h

This also made it clear that several .c files that depended upon path.h
were missing a #include for it; add the missing includes while at it.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

submodule.c

@@ -20,6 +20,7 @@
 #include "strvec.h"
 #include "blob.h"
 #include "thread-utils.h"
+#include "path.h"
 #include "quote.h"
 #include "remote.h"
 #include "worktree.h"