LINUX: Keyring deal with suse-specific key_type op

instantiate_prep used for checking for
STRUCT_KEY_TYPE_HAS_PREPARSE

Reviewed-on: http://gerrit.openafs.org/10194
Reviewed-by: Marc Dionne <marc.c.dionne@gmail.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit 9db8b123e4dab6c25ef4166ad3fa74aaa0f630f4)

Change-Id: I94e44be4d370c7096140162bea9ba1ad8fd69781
Reviewed-on: http://gerrit.openafs.org/10252
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Marc Dionne <marc.c.dionne@gmail.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>