ANDROID: vendor_hooks: add vendor hooks for bio_add_page_merge_bypass

Add a vendor hook for bio_add_page_merge_bypass. For the data partition
of "file encryption", if using the inlinecrypt path, but using CPU decryption;
If the size of the read data is 32M, the flag of "O_DIRECT" is set, and
the maximum request size of the underlying storage is 512K, when the buf page
issued by the user layer contains a large number of physically continuous parts,
it will cause the bio to become very large, even 32M. At this time, decrypting
the data will require waiting for a large number of requests to complete before
starting decryption, resulting in a serious decrease in read performance.
So it need a solution for CPU decryption to avoid merging into too large a bio.

Bug: 436447336

Change-Id: If00a8d95c0cb61f7e65ccbcd1be57d0416fbb4fb
Signed-off-by: Aran Dalton <arda@allwinnertech.com>