LU-15420 sec: fix native fscrypt builds

LU-15420 sec: fix native fscrypt builds

The recent changes in libcfs prevents native fscrypt from
building. Replace llcrypt.h with lustre_crypto.h in linux-prim.c
which will build under all conditions. We really only need
llcrypt_[init|exit] for this code. The new symlink fix for
fscrypt also breaks when building native fscrypt. Now 5.9 or
less kernels will build natively and it pass all testing.

Test-Parameters: trivial
Fixes: 209607fd79 ("LU-18096 enc: ll_get_symlink overlay function")
Change-Id: I8230364604992150da5bbfb27a3407e99e212ba6
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/57344
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>