[foreign] RFR 8217462: Add a jextract option to not generate typedef annotation interfaces

[Jorn Vernee]

Hi,

 From the bug description:

Currently jextract generates annotation interfaces for typedefs. But, 
using these annotations is not required to call the native functions 
defined in a library. Rather, they are there to add additional metadata 
to java carrier types.

Since use of these annotations interfaces is optional, it would be nice 
to have a jextract option to turn of their generation, in order to 
simplify generated classes (especially useful when viewing them with a 
decompiler/javap)

Please review the following.

Bug: https://bugs.openjdk.java.net/browse/JDK-8217462
Webrev: 
http://cr.openjdk.java.net/~jvernee/panama/webrevs/8217462/webrev.00/

Thanks,
Jorn