hg: panama/dev: 8202907: Consolidate the design and implementation of the nicl support

[maurizio.cimadamore at oracle.com]

Changeset: 2b8e82ce5bf9
Author:    mcimadamore
Date:      2018-06-22 15:25 +0100
URL:       http://hg.openjdk.java.net/panama/dev/rev/2b8e82ce5bf9

8202907: Consolidate the design and implementation of the nicl support
* switch jextract-ffi test back into JIT mode
* add support for linux includes in jextract-ffi test

! make/RunTests.gmk
! make/autoconf/lib-clang.m4
! make/autoconf/spec.gmk.in
! test/jdk/com/sun/tools/jextract/jclang-ffi/TestJextractFFI.java
! test/jdk/com/sun/tools/jextract/jclang-ffi/src/jdk/internal/clang/LibClang.java