Don't force efi to a 32-bit build on amd64

Sponsored by:	The FreeBSD Foundation

sys/boot/efi/Makefile.inc

@@ -2,17 +2,10 @@
 
 BINDIR?=	/boot
 
-.if ${MACHINE_CPUARCH} == "i386" || ${MACHINE_CPUARCH} == "amd64"
+.if ${MACHINE_CPUARCH} == "i386"
 CFLAGS+=        -march=i386
 .endif
 
-.if ${MACHINE_CPUARCH} == "amd64"
-CFLAGS+=        -m32
-ACFLAGS+=       -m32
-LDFLAGS+=       -m elf_i386_fbsd
-AFLAGS+=        --32
-.endif
-
 # Options used when building app-specific efi components
 CFLAGS+=	-ffreestanding -fshort-wchar -Wformat
 LDFLAGS+=	-nostdlib