Disable global semantic-mode key bindings

Those collide with Org's bindings for setting item prioties.

init.el

@@ -1454,9 +1454,14 @@
 
 (use-package semantic
   :commands (semantic-mode)
-  :init (setq semantic-default-submodes
-              '(global-semantic-idle-scheduler-mode
-                global-semanticdb-minor-mode))
+  :init (progn
+          (setq semantic-default-submodes
+                '(global-semantic-idle-scheduler-mode
+                  global-semanticdb-minor-mode))
+
+          ;; Disable global key bindings as we are not using them;
+          ;; cf. https://emacs.stackexchange.com/questions/32389/how-do-you-disable-all-keybinding-for-a-package
+          (setq semantic-mode-map (make-sparse-keymap)))
   :config (progn
             (require 'semantic/ia)
             (require 'semantic/bovine/el)