Fix up the template maintainer scripts

if we're not running on an EFI system then exit cleanly

debian/changelog

@@ -1,3 +1,10 @@
+shim (15.4-4) unstable; urgency=medium
+
+  * Fix up those maintainer scripts - if we're not running on an EFI
+    system then exit cleanly.
+
+ -- Steve McIntyre <93sam@debian.org>  Tue, 04 May 2021 17:53:21 +0100
+
 shim (15.4-3) unstable; urgency=medium
 
   * Add maintainer scripts to the template packages to manage

debian/signing-template/@final_pkg_name@.postinst.in

@@ -1,6 +1,11 @@
 #! /bin/sh
 set -e
 
+# If we're not on an EFI system, do nothing
+if [ ! -d /sys/firmware/efi ]; then
+    exit 0
+fi
+
 # Must load the confmodule for our template to be installed correctly.
 . /usr/share/debconf/confmodule
 
@@ -53,7 +58,6 @@ case $1 in
 	# needed
 	if [ "$bootloader_id" ] && \
 	   [ -d "/boot/efi/EFI/$bootloader_id" ] && \
-	   [ -d /sys/firmware/efi ] && \
 	   which grub-install >/dev/null 2>&1
 	then
 	    # Check for some of the options that matter, so we can

debian/signing-template/@final_pkg_name@.postrm.in

@@ -1,6 +1,11 @@
 #! /bin/sh
 set -e
 
+# If we're not on an EFI system, do nothing
+if [ ! -d /sys/firmware/efi ]; then
+    exit 0
+fi
+
 case @arch@ in
     i386)
 	SHIM_REMOVE="mmia32.efi fbia32.efi";;
@@ -39,8 +44,7 @@ case $1 in
 	# If we're being removed, remove the copies installed in the
 	# ESP. grub-install doesn't clean those up for us.
 	if [ "$bootloader_id" ] && \
-	   [ -d "/boot/efi/EFI/$bootloader_id" ] && \
-	   [ -d /sys/firmware/efi ]; then
+	   [ -d "/boot/efi/EFI/$bootloader_id" ]; then
 
 	    cd /boot/efi/EFI/$bootloader_id
 	    rm -f $SHIM_REMOVE