dracut-module-setup.sh: stop overwriting dracut's trap handler

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2149246

Latest Workstation live x86_64 image has an excess increase of ~300 MB
in size. This is because kdumpbase module's trap handler overwrites
dracut's handler and DRACUT_TMPDIR which has three unpacked initramfs
files fails to be cleaned up. This patch moves kdumpbase module's
temporary folder under DRACUT_TMPDIR and lets dracut's trap handler do
the cleanup instead.

Fixes: d25b1ee3 ("Add functions to copy NetworkManage connection profiles to the initramfs")
Signed-off-by: Coiby Xu <coxu@redhat.com>
Reviewed-by: Philipp Rudo <prudo@redhat.com>

dracut-module-setup.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-_DRACUT_KDUMP_NM_TMP_DIR="/tmp/$$-DRACUT_KDUMP_NM"
+_DRACUT_KDUMP_NM_TMP_DIR="$DRACUT_TMPDIR/$$-DRACUT_KDUMP_NM"
 
 _save_kdump_netifs() {
     unique_netifs[$1]=1
@@ -10,13 +10,6 @@ _get_kdump_netifs() {
     echo -n "${!unique_netifs[@]}"
 }
 
-cleanup() {
-    rm -rf "$_DRACUT_KDUMP_NM_TMP_DIR"
-}
-
-# shellcheck disable=SC2154 # known issue of shellcheck https://github.com/koalaman/shellcheck/issues/1299
-trap 'ret=$?; cleanup; exit $ret;' EXIT
-
 kdump_module_init() {
     if ! [[ -d "${initdir}/tmp" ]]; then
         mkdir -p "${initdir}/tmp"