How to set QAT to support symmetric encryption and decryption

I added the debug log in asynch_mode_nginx and found that SSL_read () / SSL_write () never returned SSL_ERROR_WANT_ASYNC.

In order to determine whether SSL_read / SSL_write was actually offloaded to QAT, I performed the following verification：

1.```watch -d cat /sys/kernel/debug/qat_c6xx_0000\:1a\:00.0/fw_counters``` only has the number of bytes when SSL_do_handshrk, and there is no number of bytes when SSL_read / SSL_wirte.

2. I turned on the QAT debug log (--enable-qat_debug, --with-qat_debug_file=/path/log), only the RSA asymmetric encryption information was seen in the qat debug log, and the symmetric encryption information was not seen.

Will SSL_read () / SSL_write () return SSL_ERROR_WANT_ASYNC, or will the code that handles SSL_read () / SSL_write () return SSL_ERROR_WANT_ASYNC never run?