[__lxc_container] fix some shellchecks (incl. warnings)

To the error in the `explorer/state`: It's intended, as it passes
possible parameters to the command. Varibale will set unquoted, so
word splitting take action, but the quotes inside the variable work.

cdist/conf/type/__lxc_container/explorer/state

@@ -19,12 +19,14 @@ lxcpath="$(cat "$__object/parameter/lxcpath" 2>/dev/null || true)"
 # assemble optional parameters
 LXC_PARAM=""
 if [ "$lxcpath" ]; then
+	# shellcheck disable=SC2089
 	LXC_PARAM="$LXC_PARAM -P \"$lxcpath\""
 fi
 
 
 # function to get information
 lxc_info() {
+	# shellcheck disable=SC2090 disable=SC2086
 	if [ "$user" != "$USER" ]; then
 		su -s "$(which -- lxc-info)" -- "$user" $LXC_PARAM -n "$name" -H "$@"
 	else

cdist/conf/type/__lxc_container/gencode-remote

@@ -44,7 +44,7 @@ fi
 # shortcut for checking config changes
 tmppath="$__object/files/remote-tmpfile"
 config_changes() {
-	if ( [ -f "${tmppath}_add" ] || [ -f "${tmppath}_del" ] ); then
+	if [ -f "${tmppath}_add" ] || [ -f "${tmppath}_del" ]; then
 		return 0
 	else
 		return 1
@@ -91,7 +91,7 @@ USER
 			backingstore_opts=""
 			if [ -f "$__object/parameter/backingstore" ]; then
 				# -B works for both types, they have different long opts
-				backingstore_opts="-B '$(cat "$__object/parameter/backingstore")'"
+				backingstore_opts="$backingstore_opts -B '$(cat "$__object/parameter/backingstore")'"
 
 				# add parameters if available
 				bdev_add_if_available dir
@@ -149,7 +149,7 @@ LXC
 
 				# at last, apply custom options
 				if [ -f "$__object/parameter/template-opts" ]; then
-					while read line; do
+					while read -r line; do
 						template_opts="$template_opts $line"
 					done < "$__object/parameter/template-opts"
 				fi

cdist/conf/type/__lxc_container/manifest

@@ -93,7 +93,7 @@ fi
 write_multi_param() {
 	if ! [ -f "$__object/parameter/$1" ]; then return 0; fi
 
-	while read line; do
+	while read -r line; do
 		if [ "$line" = "-" ]; then
 			# append stdin
 			cat "$__object/stdin"