setup.h: move declarations for setup.c functions from cache.h

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/http-fetch.c b/http-fetch.c
index 4549333..c874d34 100644
--- a/http-fetch.c
+++ b/http-fetch.c
@@ -5,6 +5,7 @@
 #include "hex.h"
 #include "http.h"
 #include "walker.h"
+#include "setup.h"
 #include "strvec.h"
 #include "urlmatch.h"
 #include "trace2.h"