Silence 'make checkbashisms'

Commit d2bce6d03 added the 'make checkbashisms' target but did not
resolve all of the bashisms in the scripts.  This commit doesn't
resolve them all either but it does fix up a few, and it excludes
the others so 'make checkstyle' no longer prints warnings.  It's
a small step in the right direction.

* Dracut is Linux specific and itself depends on bash.  Therefore
  all dracut support scripts can be bash specific, update their
  shebang accordingly.

* zed-functions.sh, zfs-import, zfs-mount, zfs-zed, smart
  paxcheck.sh, make_gitrev.sh - these scripts were excuded from
  the check until they can be updated and properly tested.

* zfsunlock - only whole values for sleep are allowed.

* vdev_id - removed unneeded locals; use && instead of -a.

* dkms.mkconf, dkms.postbuil - use || instead of -o.

Reviewed-by: InsanePrawn <insane.prawny@gmail.com>
Reviewed-by:  Gabriel A. Devenyi <gdevenyi@gmail.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #10755

cmd/vdev_id/vdev_id

@@ -114,9 +114,8 @@ EOF
 }
 
 map_slot() {
-	local LINUX_SLOT=$1
-	local CHANNEL=$2
-	local MAPPED_SLOT=
+	LINUX_SLOT=$1
+	CHANNEL=$2
 
 	MAPPED_SLOT=`awk "\\$1 == \"slot\" && \\$2 == ${LINUX_SLOT} && \
 			\\$4 ~ /^${CHANNEL}$|^$/ { print \\$3; exit }" $CONFIG`
@@ -127,9 +126,9 @@ map_slot() {
 }
 
 map_channel() {
-	local MAPPED_CHAN=
-	local PCI_ID=$1
-	local PORT=$2
+	MAPPED_CHAN=
+	PCI_ID=$1
+	PORT=$2
 
 	case $TOPOLOGY in
 		"sas_switch")
@@ -487,7 +486,7 @@ alias_handler () {
 	#          digits as partitions, causing alias creation to fail. This
 	#          ambiguity seems unavoidable, so devices using this facility
 	#          must not use such names.
-	local DM_PART=
+	DM_PART=
 	if echo $DM_NAME | grep -q -E 'p[0-9][0-9]*$' ; then
 		if [ "$DEVTYPE" != "partition" ] ; then
 			DM_PART=`echo $DM_NAME | awk -Fp '/p/{print "-part"$2}'`
@@ -549,7 +548,7 @@ if [ ! -r $CONFIG ] ; then
 	exit 0
 fi
 
-if [ -z "$DEV" -a -z "$ENCLOSURE_MODE" ] ; then
+if [ -z "$DEV" ] && [ -z "$ENCLOSURE_MODE" ] ; then
 	echo "Error: missing required option -d"
 	exit 1
 fi
@@ -565,7 +564,7 @@ fi
 TOPOLOGY=${TOPOLOGY:-sas_direct}
 
 # Should we create /dev/by-enclosure symlinks?
-if [ "$ENCLOSURE_MODE" = "yes" -a "$TOPOLOGY" = "sas_direct" ] ; then
+if [ "$ENCLOSURE_MODE" = "yes" ] && [ "$TOPOLOGY" = "sas_direct" ] ; then
 	ID_ENCLOSURE=$(enclosure_handler)
 	if [ -z "$ID_ENCLOSURE" ] ; then
 		exit 0