Enable TLS 1.3 middlebox compatibility by default with --enable-jni

Adding -DWOLFSSL_TLS13_MIDDLEBOX_COMPAT flag to the default
compilation flags when --enable-jni is used.

Related PRs in other repositories:
- wolfSSL/wolfssljni#255
- wolfSSL/testing#845

Author: gasbytes

configure.ac

@@ -6988,6 +6988,7 @@ then
     AM_CFLAGS="$AM_CFLAGS -DKEEP_PEER_CERT"
     AM_CFLAGS="$AM_CFLAGS -DWOLFSSL_ALWAYS_VERIFY_CB"
     AM_CFLAGS="$AM_CFLAGS -DWOLFSSL_ALWAYS_KEEP_SNI"
+    AM_CFLAGS="$AM_CFLAGS -DWOLFSSL_TLS13_MIDDLEBOX_COMPAT"
 
     # Enable prereqs if not already enabled
     if test "x$ENABLED_DTLS" = "xno"