Remove the hopelessly confused GUMSTIX.conf config

This config never worked. At no time did u-boot match the kenrel match
the userland. As all the GUMSTIX gear we support is quite old and/or
not working, remove it. The duovero stuff might work, but nobody
has the hardware for it and GUMSTIX hasn't sold it in years.

release/arm/GUMSTIX.conf

@@ -1,38 +0,0 @@
-#!/bin/sh
-#
-# $FreeBSD$
-#
-
-EMBEDDED_TARGET_ARCH="arm"
-EMBEDDED_TARGET="arm"
-EMBEDDEDBUILD=1
-EMBEDDEDPORTS="sysutils/u-boot-duovero"
-FAT_SIZE="50m"
-FAT_TYPE="16"
-IMAGE_SIZE="3072M"
-KERNEL="GUMSTIX"
-MD_ARGS="-x 63 -y 255"
-NODOC=1
-PART_SCHEME="MBR"
-
-arm_install_uboot() {
-	UBOOT_DIR="/usr/local/share/u-boot/u-boot-duovero"
-	FATMOUNT="${DESTDIR%${KERNEL}}/fat"
-	UFSMOUNT="${DESTDIR%${KERNEL}}/ufs"
-	chroot ${CHROOTDIR} mkdir -p "${FATMOUNT}" "${UFSMOUNT}"
-	chroot ${CHROOTDIR} mount_msdosfs /dev/${mddev}s1 ${FATMOUNT}
-	chroot ${CHROOTDIR} mount /dev/${mddev}s2a ${UFSMOUNT}
-	chroot ${CHROOTDIR} cp -p ${UBOOT_DIR}/MLO ${FATMOUNT}/MLO
-	chroot ${CHROOTDIR} cp -p ${UBOOT_DIR}/u-boot.img ${FATMOUNT}/u-boot.img
-	chroot ${CHROOTDIR} cp ${UBOOT_DIR}/boot.scr ${FATMOUNT}/boot.scr
-	chroot ${CHROOTDIR} cp -p ${UFSMOUNT}/boot/ubldr.bin \
-		${FATMOUNT}/ubldr.bin
-	chroot ${CHROOTDIR} touch ${UFSMOUNT}/firstboot
-	sync
-	umount_loop ${CHROOTDIR}/${FATMOUNT}
-	umount_loop ${CHROOTDIR}/${UFSMOUNT}
-	chroot ${CHROOTDIR} rmdir ${FATMOUNT}
-	chroot ${CHROOTDIR} rmdir ${UFSMOUNT}
-	
-	return 0
-}