mm/vmalloc: remove unneeded function forward declaration

The forward declaration for lazy_max_pages() is unnecessary.  Remove it.

Link: https://lkml.kernel.org/r/20220124133752.60663-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

@@ -791,7 +791,6 @@ RB_DECLARE_CALLBACKS_MAX(static, free_vmap_area_rb_augment_cb,
 
 static void purge_vmap_area_lazy(void);
 static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
-static unsigned long lazy_max_pages(void);
 
 static atomic_long_t nr_vmalloc_pages;