core/mount: correctly set DefaultDependencies=no for mounts from mountinfo

Follow-up for 3c0a1b1e70

Before this commit, DefaultDependencies=no is set in
mount_add_extras(). However, when generating mount units
from /proc/self/mountinfo, we don't have a unit in memory
yet, and mount_setup_new_unit() doesn't call into
mount_add_extras().

Fixes #32838

src/core/mount.c

@@ -604,6 +604,9 @@ static int mount_add_non_exec_dependencies(Mount *m) {
         if (!m->where)
                 return 0;
 
+        if (mount_is_credentials(m))
+                UNIT(m)->default_dependencies = false;
+
         /* Adds in all dependencies directly responsible for ordering the mount, as opposed to dependencies
          * resulting from the ExecContext and such. */
 
@@ -650,9 +653,6 @@ static int mount_add_extras(Mount *m) {
                         return r;
         }
 
-        if (mount_is_credentials(m))
-                u->default_dependencies = false;
-
         r = unit_patch_contexts(u);
         if (r < 0)
                 return r;