LU-18810 obd: add a parameter to enable filename encoding

LU-18810 obd: add a parameter to enable filename encoding

This patch adds a parameter "enable_fname_encoding" to encode
filename in the logs, uses 64-bit FNV-1a to hash filename and
uses function gss_base64url_encode() to encode the hashed
filename to the printable characters.
The following functions and macros are defined for different
pattens:
- encode_fn_len(fname, len)
- encode_fn(fname)
- encode_fn_dname(len, fname)
- encode_fn_luname(lname)
- encode_fn_opdata(op)
- encode_fn_oied(ent)
- encode_fn_qstr(qstr)
- encode_fn_dentry(dentry)
- encode_fn_file(file)

This is a port of
Lustre-change: https://review.whamcloud.com/57985
Lustre-commit: TBD (from c582a55e791fdb2967c36dbbc95fb0e8d48e6b39)
EX-bug-id: EX-11415

Signed-off-by: Emoly Liu <emoly@whamcloud.com>
Change-Id: Icf258dc3eb10b915eb7eff970bc20822daa79777
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/58433
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>