libdtsvc: Resolve coverity warnings related to 'dereference before null check' related to free()

cde/lib/DtSvc/DtEncap/connect.c

@@ -418,7 +418,7 @@ Xegetcwd(char *buf, int size)
       env = XeMalloc(MAXPATHLEN+10);
       sprintf(env, "PWD=%s", buf);
       copying_putenv(env);	/* set PWD if necessary for later cache use */
-      if (env) XeFree(env);
+      XeFree(env);
    }
    return current_dir;
 }
@@ -448,7 +448,7 @@ Xechdir (const char *path)
       }
       
       copying_putenv(env); /* update PWD if directory changed */
-      if (env) XeFree(env);
+      XeFree(env);
    }
    return status;
 }

cde/lib/DtSvc/DtEncap/noio.c

@@ -234,8 +234,7 @@ SPC_Channel_Ptr open_noio_channel_object(SPC_Channel_Ptr channel,
     else {
       temp_dir_name = get_tmp_dir ();
       channel->logfile=tempnam(temp_dir_name,"SPC");
-      if (temp_dir_name != NULL)
-        free(temp_dir_name);
+      free(temp_dir_name);
     }
 
     /*