distfile-check: add shellcheck ignores

Looks like there's a new shellscript version that finds more errors than
before. The errors are non-POSIX syntax that do work with busybox sh,
just ignore it for now since I want to fix another script.

distfile-check/distfiletree.sh

@@ -19,8 +19,10 @@ sha512sums=""
 . "$apkbuild_path"
 
 distfile_hash() {
+	# shellcheck disable=SC3043
 	local distfile="$1"
 
+	# shellcheck disable=SC3003
 	IFS=$'\n'
 	for line in $sha512sums; do
 		case "$line" in
@@ -42,7 +44,9 @@ is_remote() {
 	return 1
 }
 filename_from_uri() {
+	# shellcheck disable=SC3043
 	local uri="$1"
+	# shellcheck disable=SC3043
 	local filename="${uri##*/}"  # $(basename $uri)
 	case "$uri" in
 	*::*) filename=${uri%%::*};;