params: allow more variations in integer conversions.
params: allow more variations in integer conversions.

Allow any sized integer to be converted to any other size integer via the
helpers.

Support for converting reals to/from integers remains restricted.

Fixes: #13429

Reviewed-by: Richard Levitte <5fb523282dd7956571c80524edc2dccfa0bd8234@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/13663)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl