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)

 (C) 2007 Yann E. MORIN <yann.morin.1998@anciens.enib.fr>

 License: LGPL v2.1

 Shut off a stupid warning: preffered-stack-boundary must be between 4 ad 12,

 and 2 is not.

 diff -dur glibc-2.5.orig/sysdeps/i386/Makefile glibc-2.5/sysdeps/i386/Makefile

 --- glibc-2.5.orig/sysdeps/i386/Makefile	2005-03-06 01:18:16.000000000 +0100

 +++ glibc-2.5/sysdeps/i386/Makefile	2007-05-27 17:49:37.000000000 +0200

 @@ -36,7 +36,7 @@

  ifeq ($(subdir),csu)

  sysdep-CFLAGS += -mpreferred-stack-boundary=4

  else

 -sysdep-CFLAGS += -mpreferred-stack-boundary=2

 +sysdep-CFLAGS += -mpreferred-stack-boundary=4

  # Likewise, any function which calls user callbacks

  uses-callbacks += -mpreferred-stack-boundary=4

  # Likewise, any stack alignment tests