Trim excess shellcheck annotations. Widen to all non-Korn scripts

Before, make shellcheck checked
  scripts/{commitcheck,make_gitrev,man-dates,paxcheck,zfs-helpers,zfs,
           zfs-tests,zimport,zloop}.sh
  cmd/zed/zed.d/{{all-debug,all-syslog,data-notify,generic-notify,
                 resilver_finish-start-scrub,scrub_finish-notify,
                 statechange-led,statechange-notify,trim_finish-notify,
                 zed-functions}.sh,history_event-zfs-list-cacher.sh.in}
  cmd/zpool/zpool.d/{dm-deps,iostat,lsblk,media,ses,smart,upath}
now it also checks
  contrib/dracut/{02zfsexpandknowledge/module-setup,
                  90zfs/{export-zfs,parse-zfs,zfs-needshutdown,
                         zfs-load-key,zfs-lib,module-setup,
                         mount-zfs,zfs-generator}}.sh.in
  cmd/zed/zed.d/{pool_import-led,vdev_attach-led,
                 resilver_finish-notify,vdev_clear-led}.sh
  contrib/initramfs/{zfsunlock,hooks/zfs.in,scripts/local-top/zfs}
  tests/zfs-tests/tests/perf/scripts/prefetch_io.sh
  scripts/common.sh.in
  contrib/bpftrace/zfs-trace.sh
  autogen.sh

Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12042

contrib/dracut/90zfs/module-setup.sh.in

@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+# shellcheck disable=SC2154
 
 check() {
 	# We depend on udev-rules being loaded

contrib/dracut/90zfs/mount-zfs.sh.in

@@ -1,4 +1,5 @@
 #!/bin/sh
+# shellcheck disable=SC2034,SC2154
 
 . /lib/dracut-zfs-lib.sh
 
@@ -39,6 +40,7 @@ udevadm settle
 
 if [ "${root}" = "zfs:AUTO" ] ; then
 	if ! ZFS_DATASET="$(find_bootfs)" ; then
+		# shellcheck disable=SC2086
 		zpool import -N -a ${ZPOOL_IMPORT_OPTS}
 		if ! ZFS_DATASET="$(find_bootfs)" ; then
 			warn "ZFS: No bootfs attribute found in importable pools."

contrib/dracut/90zfs/parse-zfs.sh.in

@@ -1,4 +1,5 @@
 #!/bin/sh
+# shellcheck disable=SC2034,SC2154
 
 . /lib/dracut-lib.sh
 
@@ -28,7 +29,7 @@ case "${root}" in
 		info "ZFS: Enabling autodetection of bootfs after udev settles."
 		;;
 
-	ZFS\=*|zfs:*|zfs:FILESYSTEM\=*|FILESYSTEM\=*)
+	ZFS=*|zfs:*|FILESYSTEM=*)
 		# root is explicit ZFS root.  Parse it now.  We can handle
 		# a root=... param in any of the following formats:
 		# root=ZFS=rpool/ROOT

contrib/dracut/90zfs/zfs-generator.sh.in

@@ -1,4 +1,5 @@
 #!/bin/sh
+# shellcheck disable=SC2016,SC1004
 
 grep -wq debug /proc/cmdline && debug=1
 [ -n "$debug" ] && echo "zfs-generator: starting" >> /dev/kmsg

contrib/dracut/90zfs/zfs-lib.sh.in

@@ -59,6 +59,7 @@ import_pool() {
 
     if ! zpool list -H "${pool}" > /dev/null 2>&1; then
         info "ZFS: Importing pool ${pool}..."
+        # shellcheck disable=SC2086
         if ! zpool import -N ${ZPOOL_IMPORT_OPTS} "${pool}" ; then
             warn "ZFS: Unable to import pool ${pool}"
             return 1
@@ -123,13 +124,12 @@ for_relevant_root_children() {
 # export_all OPTS
 #   exports all imported zfs pools.
 export_all() {
-    opts="${@}"
     ret=0
 
     IFS="${NEWLINE}"
     for pool in $(zpool list -H -o name) ; do
         if zpool list -H "${pool}" > /dev/null 2>&1; then
-            zpool export "${pool}" ${opts} || ret=$?
+            zpool export "${pool}" "$@" || ret=$?
         fi
     done
     IFS="${OLDIFS}"

contrib/dracut/90zfs/zfs-load-key.sh.in

@@ -1,4 +1,5 @@
 #!/bin/sh
+# shellcheck disable=SC2154
 
 # only run this on systemd systems, we handle the decrypt in mount-zfs.sh in the mount hook otherwise
 [ -e /bin/systemctl ] || [ -e /usr/bin/systemctl ] || return 0