Makefile.in: add update-build-tools target * Makefile.in: add update-build-tools target * src/build-autoconf.mk, src/build-automake.mk, src/build-bison.mk, src/build-gawk.mk, src/build-gcc.mk, src/build-gettext.mk, src/build-gperf.mk, src/build-m4.mk, src/build-texinfo.mk, src/build-libtool.mk : update PKG_UPDATE for getting latest version from gnu.org * src/build-cmake.mk, src/build-flex.mk, src/build-lzip.mk, src/build-pkg-config.mk, src/pkg-config.mk, src/build-scons.mk : add implemented PKG_UPDATE macro

mxe.cc