debian/preinst: do a better job cleaning up artifacts

When converting to transition package, the EFI binary stopped getting
cleaned up.

Also in some cases the directories are continuing to exist in /var/lib
or /var/cache, so explicitly clean those up as well.

debian/preinst

@@ -5,5 +5,21 @@
 
 set -e
 
-rm -f /var/cache/fwupdate/done
+EFIDIR=$(dpkg-vendor --query vendor | awk '{ print tolower($$0) }')
+if [ "${DPKG_MAINTSCRIPT_ARCH}" = "amd64" ]; then
+	EFI_NAME=x64
+elif [ "${DPKG_MAINTSCRIPT_ARCH}" = "i386" ]; then
+	EFI_NAME=ia32
+elif [ "${DPKG_MAINTSCRIPT_ARCH}" = "arm64" ]; then
+	EFI_NAME=aa64
+elif [ "${DPKG_MAINTSCRIPT_ARCH}" = "armhf" ]; then
+	EFI_NAME=arm
+fi
+rm -f /boot/efi/EFI/$EFIDIR/fwup$EFI_NAME.efi
 rm -f /var/lib/fwupdate/done
+rm -f /var/cache/fwupdate/done
+for dir in /boot/efi/EFI/$EFIDIR/fw /var/cache/fwupdate /var/lib/fwupdate; do
+	if [ -d $dir ]; then
+	        rmdir --parents --ignore-fail-on-non-empty $dir || true
+	fi
+done