Fix a bunch of -Wempty-body warnings reported by clang

Many of these were real bugs, like:

if (cond);
   do_something

etc...

Others were just cosmetic - like placing the ';' on a separate line to
make the intention clear.

cde/programs/dtmail/libDtMail/Common/DtMailRc.C

@@ -2050,8 +2050,8 @@ DtMail::MailRc::expand(char *name)
 	close(pivec[1]);
 	l = read(pivec[0], xname, LINESIZE);
 	close(pivec[0]);
-	while (wait(&s) != pid);
-		;
+	while (wait(&s) != pid)
+            ;
 	s &= 0377;
 	if (s != 0 && s != SIGPIPE) {
 		fprintf(stderr, "Echo failed\n");

cde/programs/dtmail/libDtMail/Common/DtMailServer.C

@@ -789,8 +789,9 @@ DtMailServer::retrieve_messages(DtMailEnv &error)
 	if (ok != DTME_MailServerAccess_SocketIOError)
 	  if (ok == DTME_NoError)
 	    ok = ptrans_quit();
-	  else
+	  else {
 	    (void) ptrans_quit();
+          }
 	vtalarm_setitimer(0);
 	SockClose(_sockfp);
 	_sockfp = NULL;