There was a bug in both crypt_token_assign_keyslot and
crypt_token_unsassign_keyslot where CRYPT_ANY_TOKEN
special value could be passed in token parameter.
It would correctly assign/unassign all tokens to/from
the specified keyslot (or from any in case of CRYPT_ANY_SLOT),
but it returned -1 (CRYPT_ANY_TOKEN) which fited error return
values as per API documentation.
We fixed that by not supporting CRYPT_ANY_TOKEN since it does
not make much sense. It can be workarounded by iterating over
all available tokens and calling crypt_token_assign_keyslot or
crypt_token_unassign_keyslot accodingly.
Fixes: #914.
fb021bac3d