Fix RETURN VALUES for EVP_CIPHER_CTX_ctrl(3)
The current documentation was clearly incorrect since a return of -1 from
the methods is explicitly intercepted and translated to 0. schwarze and I
both audited the tree and concluded that only 0 and 1 is possible.
OpenSSL 3 broke this API contract and now has explicit return -1 in the
convoluted 200-line maze this simple function has become with recent
provider improvements. So add a small sentence hinting at that. Nobody
will be surprised to read that with OpenSSL's characteristic penchant
for needless inconsistency the return value checks in their tree are all
over the place and sometimes incorrect.
ok schwarze (with two tweaks)
UnifiedSplitRaw
