Update git to v1.7.5.4

Some changes to diff options:

- no_merges has become the more general max_parents
- path restriction now uses struct pathspec

Signed-off-by: John Keeping <john@keeping.me.uk>

shared.c

@@ -307,7 +307,7 @@ void cgit_diff_tree(const unsigned char *old_sha1,
 		    filepair_fn fn, const char *prefix, int ignorews)
 {
 	struct diff_options opt;
-	int prefixlen;
+	struct pathspec_item item;
 
 	diff_setup(&opt);
 	opt.output_format = DIFF_FORMAT_CALLBACK;
@@ -319,10 +319,10 @@ void cgit_diff_tree(const unsigned char *old_sha1,
 	opt.format_callback = cgit_diff_tree_cb;
 	opt.format_callback_data = fn;
 	if (prefix) {
-		opt.nr_paths = 1;
-		opt.paths = &prefix;
-		prefixlen = strlen(prefix);
-		opt.pathlens = &prefixlen;
+		item.match = prefix;
+		item.len = strlen(prefix);
+		opt.pathspec.nr = 1;
+		opt.pathspec.items = &item;
 	}
 	diff_setup_done(&opt);
 

ui-stats.c

@@ -239,7 +239,7 @@ struct string_list collect_stats(struct cgit_context *ctx,
 	init_revisions(&rev, NULL);
 	rev.abbrev = DEFAULT_ABBREV;
 	rev.commit_format = CMIT_FMT_DEFAULT;
-	rev.no_merges = 1;
+	rev.max_parents = 1;
 	rev.verbose_header = 1;
 	rev.show_root_diff = 0;
 	setup_revisions(argc, argv, &rev, NULL);