PVK decoder: prompt for PVK passphrase and not PEM

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from #17181)

providers/implementations/encode_decode/decode_pvk2key.c

@@ -100,7 +100,7 @@ static int pvk2key_decode(void *vctx, OSSL_CORE_BIO *cin, int selection,
         if (!ossl_pw_set_ossl_passphrase_cb(&pwdata, pw_cb, pw_cbarg))
             goto end;
 
-        key = ctx->desc->read_private_key(in, ossl_pw_pem_password, &pwdata,
+        key = ctx->desc->read_private_key(in, ossl_pw_pvk_password, &pwdata,
                                           PROV_LIBCTX_OF(ctx->provctx), NULL);
 
         /*