Re-instate the chroot by default code.

Index: pidfile.c
--- pidfile.c.orig
+++ pidfile.c
@@ -29,9 +29,10 @@
 static int pidfd = -1;
 static const char *pidname = NULL;
 
-void pidfile_create(const char *chroot_dir,
-                    const char *filename,
-                    const char *privdrop_user) {
+void
+pidfile_create(const char *chroot_dir, const char *filename,
+   const char *privdrop_user)
+{
    struct passwd *pw;
 
    if (pidfd != -1)
@@ -47,11 +48,8 @@ void pidfile_create(const char *chroot_dir,
          err(1, "getpwnam(\"%s\") failed", privdrop_user);
    }
 
-   if (chroot_dir != NULL) {
-      if (chdir(chroot_dir) == -1) {
-         err(1, "chdir(\"%s\") failed", chroot_dir);
-      }
-   }
+   if (chdir(chroot_dir) == -1)
+      err(1, "chdir(\"%s\") failed", chroot_dir);
    pidname = filename;
    pidfd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600);
    if (pidfd == -1)