Add the missing USE_QUIC_OPENSSL_COMPAT option to `make help`.
No backport needed.
# USE_OPENSSL : enable use of OpenSSL. Recommended, but see below.
# USE_OPENSSL_WOLFSSL : enable use of wolfSSL with the OpenSSL API
# USE_QUIC : enable use of QUIC with the quictls API (quictls, libressl, boringssl)
+# USE_QUIC_OPENSSL_COMPAT : enable use of QUIC with the standard openssl API (limited features)
# USE_ENGINE : enable use of OpenSSL Engine.
# USE_LUA : enable Lua support.
# USE_ACCEPT4 : enable use of accept4() on linux. Automatic.