Revert "sd-bus: check return value of asprintf()"

This reverts commit b1543c4c93.

We check b->address anyway, no need to check the return value,
especially given that the other #ifdef branch don't get the same
treatment.

src/libsystemd/sd-bus/sd-bus.c

@@ -1163,11 +1163,7 @@ int bus_set_address_user(sd_bus *b) {
 #endif
         } else {
 #ifdef ENABLE_KDBUS
-                int r;
-
-                r = asprintf(&b->address, KERNEL_USER_BUS_FMT, getuid());
-                if (r < 0)
-                        return -ENOMEM;
+                asprintf(&b->address, KERNEL_USER_BUS_FMT, getuid());
 #else
                 return -ECONNREFUSED;
 #endif