Simplify, get rid of manual _LP64 define.

Do not pass a SUN4U define, as that is no longer used in the relevant headers.
Instead tell the compiler we are compiling for a v9 CPU (so it internally
defines everything we need).

sys/arch/sparc/stand/ofwboot/Makefile

@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.34 2015/10/02 20:36:54 joerg Exp $
+#	$NetBSD: Makefile,v 1.35 2015/10/10 06:49:40 martin Exp $
 
 CURDIR=	${.CURDIR}
 S=	${CURDIR}/../../../..
@@ -15,6 +15,7 @@ SRCS=		srt0.s Locore.c boot.c ofdev.c alloc.c net.c netif_of.c vers.c
 SRCS+=		bootinfo.c loadfile_machdep.c promlib.c prf.c isfloppy.c
 .if ${MACHINE_ARCH} == "sparc64"
 SRCS+=		hvcall.S
+CPPFLAGS+=	-DSUN4V
 .endif
 .PATH:		${S}/arch/sparc64/sparc64 ${S}/arch/sparc/stand/common
 
@@ -27,11 +28,8 @@ LIBCRTEND=
 
 COPTS+=		-ffreestanding
 CWARNFLAGS+=	-Wno-main
-CFLAGS+=	${COPTS} ${CEXTRAFLAGS}
-CPPFLAGS+=	-D_STANDALONE -DSUN4U
-.if ${MACHINE_ARCH} == "sparc64"
-CPPFLAGS+=	-DSUN4V
-.endif
+CFLAGS+=	${COPTS}
+CPPFLAGS+=	-D_STANDALONE
 CPPFLAGS+=	-DBOOT_ELF32 -DBOOT_ELF64 -DBOOT_AOUT
 CPPFLAGS+=	-DNETBOOT
 CPPFLAGS+=	-DSUPPORT_DHCP
@@ -109,19 +107,9 @@ ${PROG}: ${OBJS} ${LIBSA} ${LIBZ} ${LIBKERN}
 
 .include <bsd.prog.mk>
 
-.if ${MACHINE_ARCH} == "sparc64"
+CPUFLAGS+=		-mcpu=v9
 AFLAGS+=		-Wa,-Av9a
-CEXTRAFLAGS?=		-D_LP64
-.else
-AFLAGS+=		-Wa,-Av8plusa
-.endif
-
-.if CROSS
 AFLAGS+=		-x assembler-with-cpp -D_LOCORE -D__ELF__
-CEXTRAFLAGS?=		-D_LP64
-.else
-AFLAGS+=		-x assembler-with-cpp -D_LOCORE -D__ELF__ ${CEXTRAFLAGS}
-.endif
 
 NORMAL_S=	${CC} ${AFLAGS} ${AFLAGS.${<:T}}  ${CPPFLAGS} -c $<
 srt0.o: srt0.s