Import NetBSD tools and build.sh

This commit finalizes support for cross compilation. The tools
directory are all links to the actual tools and are built on the
host system to build Minix. build.sh is the work horse that takes
care of all environment settings. It's slightly adjusted for Minix.
The /usr/src/Makefile has additional targets needed for cross
compilation.

tools/Makefile.host

@@ -0,0 +1,78 @@
+#	$NetBSD: Makefile.host,v 1.28 2011/04/10 16:52:36 joerg Exp $
+
+NOINFO=		# defined
+NOLINT=		# defined
+NOMAN=		# defined
+
+.include <bsd.own.mk>
+
+.ifndef NOCOMPATLIB
+COMPATOBJ!=	cd ${.CURDIR}/../compat && ${PRINTOBJDIR}
+.-include	"${COMPATOBJ}/defs.mk"
+.endif
+
+# Resolve pathnames in variables.
+_RESOLVE_VARS=	CFLAGS CPPFLAGS DPADD HOST_CPPFLAGS LDADD
+.for var in ${_RESOLVE_VARS}
+${var}:=	${${var}}
+.endfor
+
+# Switch over to the "real" Makefile.
+.PROGDIR:=	${.CURDIR}/../../${HOST_SRCDIR}
+_CURDIR:=	${.CURDIR}
+HOSTPROG?=	${PROG}
+
+.CURDIR:=	${.PROGDIR}
+.PATH:		${.CURDIR}
+.include "${.CURDIR}/Makefile"
+.-include "${.CURDIR}/../Makefile.inc"
+
+# Resolve pathnames from "real" Makefile, and switch .CURDIR back.
+.for var in ${_RESOLVE_VARS}
+${var}:=	${${var}}
+.endfor
+.CURDIR:=	${_CURDIR}
+.undef		_CURDIR
+
+# Set up the environment for <bsd.hostprog.mk>.
+.if ${USETOOLS} != "yes"
+.undef HOSTPROG
+.endif
+
+HOSTPROGNAME?=	${HOSTPROG}
+HOST_BINDIR?=	${TOOLDIR}/bin
+HOST_CPPFLAGS:=	${HOST_CPPFLAGS} ${CPPFLAGS}
+HOST_CPPFLAGS:=	${HOST_CPPFLAGS:N-Wp,-iremap,*:N--sysroot=*}
+.undef LINKS
+
+SRCS?=		${HOSTPROG}.c
+SRCS+=		${HOST_SRCS}
+
+.PATH:		${.PROGDIR}
+
+# Install rule.
+realinstall: install.host install.files
+install.host: ${HOST_BINDIR}/${HOSTPROGNAME}
+${HOST_BINDIR}/${HOSTPROGNAME}:: ${HOSTPROG}
+	${_MKTARGET_INSTALL}
+	mkdir -p ${HOST_BINDIR}
+	${HOST_INSTALL_FILE} -m ${BINMODE} ${HOSTPROG}${HOSTEXEEXT} ${.TARGET}
+
+.if ${MKUPDATE} == "no"
+.PHONY:		${HOST_BINDIR}/${HOSTPROGNAME}
+.endif
+
+install.files:
+.for F in ${HOSTFILES}
+install.files: ${HOST_FILESDIR}/${F}
+${HOST_FILESDIR}/${F}: ${F}
+	${_MKTARGET_INSTALL}
+	mkdir -p ${HOST_FILESDIR}
+	${HOST_INSTALL_FILE} -m ${NONBINMODE} ${.ALLSRC} ${.TARGET}
+
+.if ${MKUPDATE} == "no"
+.PHONY:		${HOST_FILESDIR}/${F}
+.endif
+.endfor
+
+.include <bsd.hostprog.mk>