Fix problem with new DCR constructor.

Coverity found a valid problem with the new DCR constructor that cannot
use the dev variable as that is a non initialized variable in the
constructor so use a proper local error buffer.

src/stored/acquire.c

@@ -636,23 +636,23 @@ bool clean_device(DCR *dcr)
  */
 DCR::DCR()
 {
+   POOL_MEM errmsg(PM_MESSAGE);
    int errstat;
 
    tid = pthread_self();
    spool_fd = -1;
    if ((errstat = pthread_mutex_init(&m_mutex, NULL)) != 0) {
       berrno be;
 
-      dev->dev_errno = errstat;
-      Mmsg1(dev->errmsg, _("Unable to init mutex: ERR=%s\n"), be.bstrerror(errstat));
-      Jmsg0(jcr, M_ERROR_TERM, 0, dev->errmsg);
+      Mmsg(errmsg, _("Unable to init mutex: ERR=%s\n"), be.bstrerror(errstat));
+      Jmsg0(jcr, M_ERROR_TERM, 0, errmsg.c_str());
    }
+
    if ((errstat = pthread_mutex_init(&r_mutex, NULL)) != 0) {
       berrno be;
 
-      dev->dev_errno = errstat;
-      Mmsg1(dev->errmsg, _("Unable to init r_mutex: ERR=%s\n"), be.bstrerror(errstat));
-      Jmsg0(jcr, M_ERROR_TERM, 0, dev->errmsg);
+      Mmsg(errmsg, _("Unable to init r_mutex: ERR=%s\n"), be.bstrerror(errstat));
+      Jmsg0(jcr, M_ERROR_TERM, 0, errmsg.c_str());
    }
 }
 

src/stored/askdir.c

@@ -598,7 +598,7 @@ bool SD_DCR::dir_ask_sysop_to_mount_volume(int mode)
       return false;
    }
    ASSERT(dev->blocked());
-   for ( ;; ) {
+   while (1) {
       if (job_canceled(jcr)) {
          Mmsg(dev->errmsg, _("Job %s canceled while waiting for mount on Storage Device %s.\n"),
               jcr->Job, dev->print_name());