Untangle building of AMD64 boot code.

Tested on:	amd64 (sledge)

sys/boot/Makefile

@@ -1,9 +1,5 @@
 # $FreeBSD$
 
-.if ${MACHINE_ARCH} == "amd64"
-.MAKEFLAGS:  MACHINE_ARCH=i386 MACHINE=i386 REALLY_AMD64=true
-.endif
-
 .if !defined(NOFORTH)
 # Build the add-in FORTH interpreter.
 SUBDIR+=		ficl
@@ -15,7 +11,7 @@ SUBDIR+=		ofw
 .endif
 
 # Pick the machine-dependent subdir based on the target architecture.
-SUBDIR+=		${MACHINE}
+SUBDIR+=		${MACHINE:S/amd64/i386/}
 
 # Build ARC / AlphaBIOS executable on the Alpha
 # (this is a WIP (work in progress)).

sys/boot/ficl/Makefile

@@ -1,10 +1,6 @@
 # $FreeBSD$
 #
-.if ${MACHINE_ARCH} == "amd64"
-.MAKEFLAGS:  MACHINE_ARCH=i386 MACHINE=i386 REALLY_AMD64=true
-.endif
-
-.PATH: ${.CURDIR}/${MACHINE_ARCH}
+.PATH: ${.CURDIR}/${MACHINE_ARCH:S/amd64/i386/}
 BASE_SRCS=	dict.c ficl.c fileaccess.c float.c loader.c math64.c \
 		prefix.c search.c stack.c tools.c vm.c words.c
 
@@ -14,7 +10,7 @@ CFLAGS+=	-ffreestanding
 .if ${MACHINE_ARCH} == "alpha"
 CFLAGS+=	-mno-fp-regs
 .endif
-.if ${MACHINE_ARCH} == "i386"
+.if ${MACHINE_ARCH} == "i386" || ${MACHINE_ARCH} == "amd64"
 CFLAGS+=	-mpreferred-stack-boundary=2
 .endif
 .if ${MACHINE_ARCH} == "powerpc"
@@ -44,17 +40,18 @@ SOFTWORDS=	softcore.fr jhlocal.fr marker.fr freebsd.fr ficllocal.fr \
 # Optional OO extension softwords
 #SOFTWORDS+=	oo.fr classes.fr
 
-.if defined(REALLY_AMD64)
+.if ${MACHINE_ARCH} == "amd64"
 CFLAGS+=	-m32 -I.
 .endif
 
-CFLAGS+=	-I${.CURDIR} -I${.CURDIR}/${MACHINE_ARCH} -I${.CURDIR}/../common
+CFLAGS+=	-I${.CURDIR} -I${.CURDIR}/${MACHINE_ARCH:S/amd64/i386/} \
+		-I${.CURDIR}/../common
 
 softcore.c: ${SOFTWORDS} softcore.awk
 	(cd ${.CURDIR}/softwords; cat ${SOFTWORDS} \
 	    | awk -f softcore.awk -v datestamp="`LC_ALL=C date`") > ${.TARGET}
 
-.if defined(REALLY_AMD64)
+.if ${MACHINE_ARCH} == "amd64"
 ${SRCS:M*.c:R:S/$/.o/g}: machine
 
 beforedepend ${OBJS}: machine

sys/boot/i386/Makefile.inc

@@ -8,10 +8,6 @@ LOADER_ADDRESS?=0x200000
 CFLAGS+=	-ffreestanding -mpreferred-stack-boundary=2
 
 .if ${MACHINE_ARCH} == "amd64"
-.MAKEFLAGS:  MACHINE_ARCH=i386 MACHINE=i386 REALLY_AMD64=true
-.endif
-
-.if defined(REALLY_AMD64)
 CFLAGS+=	-m32
 LDFLAGS+=	-m elf_i386_fbsd
 AFLAGS+=	--32

sys/boot/i386/boot2/Makefile

@@ -93,13 +93,11 @@ boot2.h: boot1.out
 	    ORG1=`printf "%d" ${ORG1}` \
 	    REL1=`printf "%d" ${REL1}` > ${.TARGET}
 
-.if defined(REALLY_AMD64)
+.if ${MACHINE_ARCH} == "amd64"
 boot2.s: machine
-
+CLEANFILES+=	machine
 machine:
 	ln -sf ${.CURDIR}/../../../i386/include machine
-
-CLEANFILES+=	machine
 .endif
 
 .include <bsd.prog.mk>

sys/boot/i386/gptboot/Makefile

@@ -93,13 +93,11 @@ boot2.h: boot1.out
 	    ORG1=`printf "%d" ${ORG1}` \
 	    REL1=`printf "%d" ${REL1}` > ${.TARGET}
 
-.if defined(REALLY_AMD64)
+.if ${MACHINE_ARCH} == "amd64"
 boot2.s: machine
-
+CLEANFILES+=	machine
 machine:
 	ln -sf ${.CURDIR}/../../../i386/include machine
-
-CLEANFILES+=	machine
 .endif
 
 .include <bsd.prog.mk>

sys/boot/i386/libi386/Makefile

@@ -33,7 +33,7 @@ CFLAGS+=	-I${.CURDIR}/../../../../lib/libstand/
 
 .include <bsd.lib.mk>
 
-.if defined(REALLY_AMD64)
+.if ${MACHINE_ARCH} == "amd64"
 ${OBJS}: machine
 CLEANFILES+=	machine
 machine:

sys/boot/i386/loader/Makefile

@@ -96,7 +96,7 @@ loader.sym: ${OBJS} ${LIBFICL} ${LIBI386} ${LIBSTAND}
 	${CC} ${LDFLAGS} -o ${.TARGET} ${BTXCRT} ${OBJS} \
 		${LIBFICL} ${LIBI386} ${LIBSTAND}
 
-.if defined(REALLY_AMD64)
+.if ${MACHINE_ARCH} == "amd64"
 ${OBJS}: machine
 CLEANFILES+=	machine
 machine: