Make unpack_trees_options bit flags actual bitfields

Instead of wasting space with whole integers for a single bit.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

unpack-trees.h

@@ -9,16 +9,16 @@ typedef int (*merge_fn_t)(struct cache_entry **src,
 		struct unpack_trees_options *options);
 
 struct unpack_trees_options {
-	int reset;
-	int merge;
-	int update;
-	int index_only;
-	int nontrivial_merge;
-	int trivial_merges_only;
-	int verbose_update;
-	int aggressive;
-	int skip_unmerged;
-	int gently;
+	unsigned int reset:1,
+		     merge:1,
+		     update:1,
+		     index_only:1,
+		     nontrivial_merge:1,
+		     trivial_merges_only:1,
+		     verbose_update:1,
+		     aggressive:1,
+		     skip_unmerged:1,
+		     gently:1;
 	const char *prefix;
 	int pos;
 	struct dir_struct *dir;