Add pstore-RAM support and fix comments indentation

Check README.MD and /etc/default/kdump for instructions on
pstore usage - should be simple, it's automatically configured.

Notice that we expect all units to have the same e820 memory
map, hence to have the RAM buffer available. This point should
be better clarified by the team working with firmware.

Also, the package now enables the kdump systemd service
automatically, in a post-installer hook.

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

README.md

@@ -15,10 +15,13 @@
 #  collection, that only grabs dmesg, and a more complete setting to grab the
 #  whole (compressed) vmcore. The tunnings are available at /etc/default/kdump.
 #
+#  Also, the infrastructure is able to configure and save pstore-RAM logs.
+#
 #  After installation and a reboot, things should be all set EXCEPT for GRUB
 #  config - please check the CAVEATS/INSTRUCTIONS section below. Notice the
-#  package is under active development, this one being a kind of "Proof Of Concept"
-#  still - improvements are expected in the near future. Thanks for testing!!!
+#  package is under active development, this version should still be considered
+#  a kind of "Proof Of Concept" - improvements are expected in the near future.
+#  Thanks for testing!!!
 #
 #
 #  CAVEATS / INSTRUCTIONS
@@ -28,6 +31,8 @@
 #  to your GRUB config in order subsequent boots pick this setting and do reserve
 #  the memory, or else kdump cannot work. The memory amount was empirically
 #  determined - 128M wasn't enough and 144M is unstable, so 160M seems good enough.
+#  If you prefer to rely on pstore-RAM, no GRUB setting should be required; this
+#  is currently the default (see /etc/default/kdump).
 #
 #  (b) It requires (obviously) a RW rootfs - we've used tune2fs in order to make
 #  it read-write, since it's RO by default. Also, we assume the nvme partition
@@ -39,13 +44,11 @@
 #  are recreated - this is not necessary, we're thinking on how to prevent that,
 #  but for now be prepared: the installation take some (long) minutes due to that ={
 #
-#  (d) Unfortunately makedumpfile form Arch Linux is not available on official
-#  repos, only in AUR - and it doesn't build with zstd, which allows great and
-#  fast compression. So, we're hereby _packing the binary_ with all the scripts,
+#  (d) Unfortunately makedumpfile from Arch Linux is not available on official
+#  repos, only in AUR. So, we're hereby _packing the binary_ with all the scripts,
 #  which is a temporary workaround and should be resolved later - already started
-#  to "lobby" for package inclusion in the official channels and also we're trying
-#  to to add zstd support:
-#  https://aur.archlinux.org/packages/makedumpfile/#comment-841333
+#  to "lobby" for package inclusion in the official channels:
+#  https://aur.archlinux.org/packages/makedumpfile/#comment-843853
 #
 #
 #  TODOs (for now - we expect to have more after some testing by the colleagues)
@@ -55,7 +58,7 @@
 #  to be added to the package.
 #
 #  (2) Hopefully we can fix/prevent the unnecessary re-creation of all initramfs
-#  images - this happens due to our package installing files on /usr/lib/dracut/modules.d
+#  images - it happens due to our pkg installing files on /usr/lib/dracut/modules.d
 #  which is a trigger for this initramfs recreation.
 #
 #  (3) We have a "fragile" way of determining a mount point required for kdump;
@@ -69,4 +72,9 @@
 #  specified kernel, not only for the running one (which is what we do now).
 #  Low-priority idea, easy to implement.
 #
+#  (6) Pstore ramoops backend has some limitations that we're discussing with
+#  the kernel community - right now we can only collect ONE dmesg and its
+#  size is truncated on "record_size" bytes, not allowing a file split like
+#  efi-pstore; hopefully we can improve that.
+#
 ```