[console] move the history buffer into static memory, remove console_init

No need to malloc this memory if it's always going to be initialized
anyway. Add history disabling switch to a few targets to make sure both
builds are tested.

app/shell/shell.c

@@ -9,16 +9,11 @@
 #include <lk/debug.h>
 #include <lib/console.h>
 
-static void shell_init(const struct app_descriptor *app) {
-    console_init();
-}
-
 static void shell_entry(const struct app_descriptor *app, void *args) {
     console_start();
 }
 
 APP_START(shell)
-.init = shell_init,
 .entry = shell_entry,
 APP_END