mac: ignore resource fork when checking file sizes

Some evil evil awful tool adds resource forks to files it's comparing.
Our Mac-specific code to do bulk stats was accidentally using "total
size" which includes those forks in the file size, causing them to be
reported as modified. This changes it to only care about the normal
data size and thus agree with what Mercurial's expecting.

mercurial/osutil.c

@@ -458,7 +458,7 b' static PyObject *_listdir_batch(char *pa'
 	requested_attr.bitmapcount = ATTR_BIT_MAP_COUNT;
 	requested_attr.commonattr = (ATTR_CMN_NAME | ATTR_CMN_OBJTYPE |
 				     ATTR_CMN_MODTIME | ATTR_CMN_ACCESSMASK);
-	requested_attr.fileattr = ATTR_FILE_TOTALSIZE;
+	requested_attr.fileattr = ATTR_FILE_DATALENGTH;
 
 	*fallback = false;