RFR: JDK-8138761 Improved handling of libffi, and cleanup of libraries.m4

Fri Oct 2 14:58:57 UTC 2015

To build zero, we need libffi. However, the code in configure to handle 
libffi is not up to normal library handling standards, so it is not 
possible to set it using configure arguments.

When trying to rectify this, I finally got tired of the mess that 
libraries.m4 is. I have split it into parts, where each prominent 
library gets it's own file, and I've switched the logic on dependencies 
to be positive (i.e. linux needs alsa, not "macosx does NOT need alsa").

The cleanup includes:
* Split libraries.m4.
* Remove builddeps.
* Remove last references to pulse.
* Remove HAVE_ALTZONE.
* Separate handling of bundled libs.
* Set LIBM properly.

The libffi support means that we now have --with-libffi[-libs/-include], 
just like for other libraries. Also, we sanity check that we can 
actually compile with libffi.

Bug: https://bugs.openjdk.java.net/browse/JDK-8138761
WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8138761-libffi-and-libraries-cleanup/webrev.01

/Magnus