ECX/ED keymanager param getter fixes.

ECX/ED keymanager param getter fixes.

Fixes #28034

ECX and ED were sharing the same code for the getter, whilst also
maintaining seperate gettable tables.

The code has been reworked so that common code is shared, and algorithm
specific code is seperated out to make this clearer.

This fixes:
(1) The security category not being in the gettable table for ED
(2) The fips indicator for ED. i.e There is no fips indicator for ED
(previously there was no gettable, but the get() still tried to return
unapproved).

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <ppzgs1@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/28039)