Don't throw error if elfeed org file does not exist

The user may not want an org file, so we shouldn't impose this error on
them if one doesn't exist.

modules/app/rss/config.el

@@ -66,7 +66,8 @@ easier to scroll through.")
   :init
   (setq rmh-elfeed-org-files (list "elfeed.org"))
   :config
-  (let ((default-directory org-directory))
-    (setq rmh-elfeed-org-files
-          (mapcar #'expand-file-name rmh-elfeed-org-files)))
-  (elfeed-org))
+  (and (let ((default-directory org-directory))
+         (setq rmh-elfeed-org-files
+               (cl-remove-if-not
+                #'file-exists-p (mapcar #'expand-file-name rmh-elfeed-org-files))))
+       (elfeed-org)))