[PATCH 4/4] eppic/keyring: Introduce changes for kernel 4.4

Linux kernel commit 146aa8b1453b ("KEYS: Merge the type-specific data
with the payload data") merges the type-specific data with the payload
data. Introduce these changes to access type/payload data and scrub
the key type.

These changes are not compatible with previous kernel versions,
so add new keyring script file for kernel version >= 4.4 and
kernel version <= 4.8.

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com>