Fix fd/rtags on debian/ubuntu

On debian/ubuntu, these executables have a different name:

- fd -> fdfind
- rc -> rtags-rc
- rdm -> rtags-rdm

modules/lang/cc/config.el

@@ -197,6 +197,11 @@ This is ignored by ccls.")
         (cond ((featurep! :completion ivy)  'ivy)
               ((featurep! :completion helm) 'helm)
               ('default))
+        ;; These executables are named rtags-* on debian
+        rtags-rc-binary-name
+        (cl-find-if #'executable-find (list rtags-rc-binary-name "rtags-rc"))
+        rtags-rdm-binary-name
+        (cl-find-if #'executable-find (list rtags-rdm-binary-name "rtags-rdm"))
         ;; If not using ivy or helm to view results, use a pop-up window rather
         ;; than displaying it in the current window...
         rtags-results-buffer-other-window t