Add unbind_nvme.sh script.

This will rmmod nvme on Linux, and use the DPDK nic_uio driver
to unbind nvme devices from the nvme driver on FreeBSD.

"nic_uio" is actually a misnomer - it is not NIC driver specific,
and can safely be used to bind NVMe devices to an effectively
null driver.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I8b964a070586166d762d79696385b82eeb2e88bd

scripts/unbind_nvme.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+set -e
+
+function configure_linux {
+	lsmod | grep nvme && rmmod nvme
+}
+
+function configure_freebsd {
+	TMP=`mktemp`
+	AWK_PROG="{if (count > 0) printf \",\"; printf \"%s:%s:%s\",\$2,\$3,\$4; count++}"
+	echo $AWK_PROG > $TMP
+	NVME_PCICONF=`pciconf -l | grep class=0x010802`
+	BDFS=`echo $NVME_PCICONF | awk -F: -f $TMP`
+	kenv hw.nic_uio.bdfs=$BDFS
+	kldload `find . -name nic_uio.ko | head -1`
+	rm $TMP
+}
+
+if [ `uname` = Linux ]; then
+	configure_linux
+else
+	configure_freebsd
+fi
+