virt: also check if PID1 is in chroot

In PID1, running_in_chroot() is called by safety_checks(), but without
this change, the check did nothing.

src/basic/virt.c

@@ -886,15 +886,15 @@ int running_in_chroot(void) {
         if (getenv_bool("SYSTEMD_IGNORE_CHROOT") > 0)
                 return 0;
 
-        if (getpid_cached() == 1)
-                return false;  /* We're PID 1, we can't be in a chroot. */
-
         r = inode_same("/proc/1/root", "/", 0);
         if (r == -ENOENT) {
                 r = proc_mounted();
                 if (r == 0) {
+                        if (getpid_cached() == 1)
+                                return false; /* We will mount /proc, assuming we're not in a chroot. */
+
                         log_debug("/proc is not mounted, assuming we're in a chroot.");
-                        return 1;
+                        return true;
                 }
                 if (r > 0)  /* If we have fake /proc/, we can't do the check properly. */
                         return -ENOSYS;