use CALLOC_ARRAY

Add and apply a semantic patch for converting code that open-codes
CALLOC_ARRAY to use it instead.  It shortens the code and infers the
element size automatically.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

bloom.c

@@ -277,7 +277,7 @@ struct bloom_filter *get_or_compute_bloom_filter(struct repository *r,
 				*computed |= BLOOM_TRUNC_EMPTY;
 			filter->len = 1;
 		}
-		filter->data = xcalloc(filter->len, sizeof(unsigned char));
+		CALLOC_ARRAY(filter->data, filter->len);
 
 		hashmap_for_each_entry(&pathmap, &iter, e, entry) {
 			struct bloom_key key;