While PCT on import has been removed for DH, EC, RSA, and SLH-DSA,
ECX seems to be overlooked. Correct that omission.
Complements: 7f7f75816f "import pct: remove import PCTs for most algorithms"
Signed-off-by: Eugene Syromiatnikov <esyr@openssl.org>
Reviewed-by: Paul Dale <ppzgs1@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/28573)