ANDROID: vendor_hook: Add hook to update nr_swap_pages and total_swap_pages

The specified swap is regarded as reserved extended memory.
So nr_swap_pages and total_swap_pages should not be affected
by the specified swap.

Provide a vendor hook android_vh_account_swap_pages to replace
the updating process of nr_swap_pages and total_swap_pages.
When the page is swapped to the specified swap location,
nr_swap_pages and total_swap_pages should not be updated.

Bug: 234214858
Signed-off-by: Bing Han <bing.han@transsion.com>
Change-Id: Ib8dfb355d190399a037b9d9eda478a81c436e224