complibs/ppl: fix 0.11-0.11.2 to compile with --disable-shared

PPL 0.11 (through 0.11.2) had a small bug where it still tried to build
and test its Java interface even when shared libraries are disabled.
Since that's exactly what ct-ng does, it explodes.

This is the patch from the PPL authors (see final link below).

More information can be found in these messages/threads:

Anthony's initial report and analysis with Yann:
http://www.cygwin.com/ml/crossgcc/2011-05/msg00046.html

Ron Flory hit the same problem:
http://www.cygwin.com/ml/crossgcc/2011-05/msg00054.html

Anthony's report to the ppl-devel list:
http://www.cs.unipr.it/pipermail/ppl-devel/2011-May/017450.html

Roberto's reply with a link to the fix in the PPL git repo:
http://www.cs.unipr.it/pipermail/ppl-devel/2011-May/017455.html

Signed-Off-By: Anthony Foiani <anthony.foiani@gmail.com>
(transplanted from 139b85d70b623e51f7585e7c64ecb8c6a6cf4567)

diff -dur strace-4.5.16.orig/system.c strace-4.5.16/system.c

--- strace-4.5.16.orig/system.c	2007-01-17 00:22:36.000000000 +0100

+++ strace-4.5.16/system.c	2007-07-14 19:28:41.000000000 +0200

@@ -1612,7 +1612,9 @@

 	{ CTL_KERN, "CTL_KERN" },

 	{ CTL_VM, "CTL_VM" },

 	{ CTL_NET, "CTL_NET" },

+#ifdef CTL_PROC

 	{ CTL_PROC, "CTL_PROC" },

+#endif

 	{ CTL_FS, "CTL_FS" },

 	{ CTL_DEBUG, "CTL_DEBUG" },

 	{ CTL_DEV, "CTL_DEV" },