Fix endianness problem in params_api_test

Fix endianness problem in params_api_test

On a big endian machine, we get test failures in params_api_test like

        # ERROR: (memory) 'buf1 == buf2' failed @ test/params_api_test.c:473
        # --- buf1
        # +++ buf2
        # 0000:-e901
        # 0000:+01e9
        #       ^^^^
        #
        # OPENSSL_TEST_RAND_ORDER=1643313367
        not ok 157 - iteration 3

They are due to an additional conversion copy.  Remove this copy to solve the
problem.

Signed-off-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17608)