util-lib: split out allocation calls into alloc-util.[ch]

src/basic/bitmap.c

@@ -19,9 +19,9 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include "util.h"
-
+#include "alloc-util.h"
 #include "bitmap.h"
+#include "util.h"
 
 struct Bitmap {
         uint64_t *bitmaps;