all: Move the multi-configuration file reading routine to a common helper

Based on Emil's (xexaxo) feedback, we now have a common.sh file
that contains the implementation of the routine to read all config
files for kdump/pstore, and we use Makefile to join the files,
having the same implemention in all users.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>

module-setup.sh.in

@@ -0,0 +1,42 @@
+#  Only include kdump if it is explicitly asked in the argument list
+check() {
+	return 255
+}
+
+installkernel() {
+	hostonly='' instmods ext4
+}
+
+install() {
+	# A valid makedumpfile is essential for the kdump initrd creation.
+	if [ ! -x "$(command -v makedumpfile)" ]; then
+		logger "kdump: failed to create initrd, makedumpfile is missing"
+		exit 1
+	fi
+
+	load_kdump_config
+
+	#  First clear all unnecessary firmwares/drivers added by drm in order
+	#  to reduce the size of the minimal initramfs being created. This
+	#  should be already done via dracut cmdline arguments, but let's play
+	#  safe and delete from here as well just in case.
+	rm -rf "$initdir"/usr/lib/firmware/amdgpu/
+	rm -rf "$initdir"/usr/lib/modules/*/kernel/drivers/gpu/drm/amd/*
+
+	#  Install necessary binaries
+	inst date
+	inst sync
+	inst makedumpfile
+
+	mkdir -p "$initdir"/usr/share/kdump.d/
+	cp -LR --preserve=all /usr/share/kdump.d/* "$initdir"/usr/share/kdump.d/
+
+	#  Determine the numerical devnode for kdump, and save it on initrd;
+	#  notice that partset link is not available that early in boot time.
+	DEVN="$(readlink -f "${MOUNT_DEVNODE}")"
+	echo "${DEVN}" > "$initdir"/usr/lib/kdump/kdump.devnode
+
+	cp -LR --preserve=all /usr/lib/kdump/* "$initdir"/usr/lib/kdump/
+
+	inst_hook pre-mount 01 "$moddir/kdump-collect.sh"
+}