alloc: add repository argument to alloc_report

This is a small mechanical change; it doesn't change the
implementation to handle repositories other than the_repository yet.
Use a macro to catch callers passing a repository other than
the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

alloc.c

@@ -105,7 +105,7 @@ static void report(const char *name, unsigned int count, size_t size)
 #define REPORT(name, type)	\
     report(#name, name##_state.count, name##_state.count * sizeof(type) >> 10)
 
-void alloc_report(void)
+void alloc_report_the_repository(void)
 {
 	REPORT(blob, struct blob);
 	REPORT(tree, struct tree);