Crypto: Use SECP256R1 key in ECDH test

Use a SECP256R1 key instead of SECP384R1 key in the
ECDH test so that both profile_large and profile_medium
can pass the test.

Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
Change-Id: Ib22533255160e989472a9a9b6979b327cacd6765
1 file changed