xentools45 fails to build on NetBSD 7 - amd64

[Louis Guillaume <louis%zabrico.com@localhost>]

Here's the error. This is with the pkgsrc-2015Q3 branch, NetBSD-7/amd64. 
The build machine is running a XEN3_DOMU kernel, if that matters.

gmake[9]: Entering directory 
'/usr/pkgobj/sysutils/xentools45/default/xen-4.5.1/tools/firmware/rombios/32bit/tcgbios'
gcc -I/usr/include -I/usr/pkg/include  -O1 -fno-omit-frame-pointer -m32 
-march=i686 -g -fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes 
 -Wdeclaration-after-statement -Wno-unused-but-set-variable 
-Wno-unused-local-typedefs   -D__XEN_TOOLS__ -MMD -MF .tcgbios.o.d 
-fno-optimize-sibling-calls -mno-tls-direct-seg-refs  -Werror 
-fno-stack-protector -fno-exceptions -fno-builtin -msoft-float 
-I/usr/pkgobj/sysutils/xentools45/default/xen-4.5.1/tools/firmware/rombios/32bit/tcgbios/../../../../../tools/include 
-I.. -I../..  -c -o tcgbios.o tcgbios.c
tcgbios.c:1:0: error: CPU you selected does not support x86-64 
instruction set


Louis