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

src/hostname/hostnamectl.c

@@ -28,6 +28,7 @@
 #include "sd-bus.h"
 #include "sd-id128.h"
 
+#include "alloc-util.h"
 #include "architecture.h"
 #include "bus-error.h"
 #include "bus-util.h"

src/hostname/hostnamed.c

@@ -24,6 +24,7 @@
 #include <unistd.h>
 #include <sys/utsname.h>
 
+#include "alloc-util.h"
 #include "bus-util.h"
 #include "def.h"
 #include "env-util.h"