- look at target variants when determining if syslinux is supported or not.

  Closes #637

target/x86/syslinux/syslinux.mk

@@ -1,4 +1,21 @@
+SYSLINUX_SUPPORTED_ARCH=n
 ifeq ($(ARCH),i386)
+SYSLINUX_SUPPORTED_ARCH=y
+endif
+ifeq ($(ARCH),i486)
+SYSLINUX_SUPPORTED_ARCH=y
+endif
+ifeq ($(ARCH),i586)
+SYSLINUX_SUPPORTED_ARCH=y
+endif
+ifeq ($(ARCH),i686)
+SYSLINUX_SUPPORTED_ARCH=y
+endif
+ifeq ($(ARCH),x86_64)
+SYSLINUX_SUPPORTED_ARCH=y
+endif
+ifeq ($(SYSLINUX_SUPPORTED_ARCH),y)
+
 #############################################################
 #
 # syslinux to make target msdos/iso9660 filesystems bootable