Enable hardware based FBE on f2fs and adapt ext4 fs

Hardware File Based Encryption (FBE) uses inline crypto
engine to encrypt the user data.
1. security/pfk: changes to support per file
   encryption for f2fs using hardware crypto engine.
2. fs/ext4: adapted crypto APIs for generic crypto layer.
3. fs/f2fs: support hardware crypto engine based per file
   encryption.
4. fs/crypto: export APIs to support hardware crypto
   engine based per file encryption.
5. security/pfe: added wrapped key support based on
   upstream changes.
Other changes made to provide support framework for per
file encryption.

Reverting commit e02a4e21 ("ext4: Add HW File Based
Encryption on ext4 file system") and adding changes to
have FBE in sync with upstream implementation of FBE.

Change-Id: I17f9909c43ba744eb874f6d237745fbf88a2b848
Signed-off-by: Shivaprasad Hongal <shongal@codeaurora.org>