complibs/ppl: fix build when local system has libgmp already installed

Basically, the ppl configure script wasn't properly setting
CFLAGS/CXXFLAGS/LDFLAGS to point at the ctng-built gmp, so ppl tried to
use the system gmp headers instead.

This patch fixes that for all PPL versions supported by crosstools-ng.

Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
[yann.morin.1998@free.fr: slightly touch the commit log]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Message-Id: <20130715230656.GB23382@shaftnet.org>
Patchwork-Id: 259300

# This file declares functions to install the kernel headers for mingw64

# Copyright 2012 Yann Diorcet

# Licensed under the GPL v2. See COPYING in the root of this package

CT_DoKernelTupleValues() {

    # Even we compile for x86_64 target architecture, the target OS have to

    # bet mingw32 (require by gcc and mingw-w64)

    CT_TARGET_KERNEL="mingw32"

    CT_TARGET_SYS=

}

do_kernel_get() {

    :

}

do_kernel_extract() {

    :

}

do_kernel_headers() {

   :

}