staging: android: Remove BUG_ON from ion_page_pool.c

BUG_ON() is removed at ion_page_pool.c

Fixes the following issue:
Avoid crashing the kernel - try using WARN_ON & recovery code ratherthan BUG() or BUG_ON().

Signed-off-by: Tomer Samara <tomersamara98@gmail.com>

drivers/staging/android/ion/ion_page_pool.c

@@ -46,11 +46,9 @@ static struct page *ion_page_pool_remove(struct ion_page_pool *pool, bool high)
 	struct page *page;
 
 	if (high) {
-		BUG_ON(!pool->high_count);
 		page = list_first_entry(&pool->high_items, struct page, lru);
 		pool->high_count--;
 	} else {
-		BUG_ON(!pool->low_count);
 		page = list_first_entry(&pool->low_items, struct page, lru);
 		pool->low_count--;
 	}
@@ -65,8 +63,6 @@ struct page *ion_page_pool_alloc(struct ion_page_pool *pool)
 {
 	struct page *page = NULL;
 
-	BUG_ON(!pool);
-
 	mutex_lock(&pool->mutex);
 	if (pool->high_count)
 		page = ion_page_pool_remove(pool, true);
@@ -82,7 +78,7 @@ struct page *ion_page_pool_alloc(struct ion_page_pool *pool)
 
 void ion_page_pool_free(struct ion_page_pool *pool, struct page *page)
 {
-	BUG_ON(pool->order != compound_order(page));
+	WARN_ON(pool->order != compound_order(page))
 
 	ion_page_pool_add(pool, page);
 }