Docs/releases: Update board support doc for 4.17 & 4.18 branches

Add the list of boards removed after the 4.18 release and update
other text.

Signed-off-by: Martin Roth <gaumless@gmail.com>
Change-Id: Id90a84eb9a417836a7d3fdd9b6f2f3ae34c95fc4
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71530
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <felixsinger@posteo.net>
diff --git a/Documentation/releases/boards_supported_on_branches.md b/Documentation/releases/boards_supported_on_branches.md
index 35f0445..2f1193b 100644
--- a/Documentation/releases/boards_supported_on_branches.md
+++ b/Documentation/releases/boards_supported_on_branches.md
@@ -12,16 +12,59 @@
 
 Currently, [jenkins](https://qa.coreboot.org), our continuous
 integration system is configured to build the 4.11, 4.12, 4.14, 4.15,
-and 4.16 branches.  Builders for other branches can be created on
+4.16, and 4.18 branches.  Builders for other branches can be created on
 request.  Likewise, some releases are only marked with tags, and
 branches would need to be created to push new code to.  These branches
 can also be created on request.
 
 Patches can be backported from the master branch to any of these other
-branches as needed. The coreboot project will take care of backporting
+branches as needed. The coreboot project may take care of backporting
 critical security fixes, but other patches will need to handled by
 anyone using that release.
 
+
+## [4.18 Release](coreboot-4.18-relnotes.md)
+Branch created, builder configured
+
+```eval_rst
++-------------------------------+------------------------+------------+-----------+
+| Vendor/Board                  | Processor              | Date added | Brd type  |
++===============================+========================+============+===========+
+| amd/inagua                    | AMD_FAMILY14           | 2011-02-14 | eval      |
+| amd/olivehill                 | AMD_FAMILY16_KB        | 2013-08-05 | eval      |
+| amd/parmer                    | AMD_FAMILY15_TN        | 2012-07-22 | eval      |
+| amd/persimmon                 | AMD_FAMILY14           | 2011-02-14 | eval      |
+| amd/south_station             | AMD_FAMILY14           | 2011-11-18 | eval      |
+| amd/thatcher                  | AMD_FAMILY15_TN        | 2012-08-02 | eval      |
+| amd/union_station             | AMD_FAMILY14           | 2011-11-18 | eval      |
+| asrock/e350m1                 | AMD_FAMILY14           | 2011-02-24 | mini      |
+| asrock/imb-a180               | AMD_FAMILY16_KB        | 2013-08-27 | mini      |
+| asus/a88xm-e                  | AMD_FAMILY15_TN        | 2020-08-13 | desktop   |
+| asus/am1i-a                   | AMD_FAMILY16_KB        | 2018-01-14 | mini      |
+| asus/f2a85-m                  | AMD_FAMILY15_TN        | 2013-03-22 | desktop   |
+| bap/ode_e20XX                 | AMD_FAMILY16_KB        | 2015-05-27 | eval      |
+| biostar/a68n_5200             | AMD_FAMILY16_KB        | 2017-10-14 | eval      |
+| biostar/am1ml                 | AMD_FAMILY16_KB        | 2015-04-10 | mini      |
+| elmex/pcm205400               | AMD_FAMILY14           | 2016-09-29 | sbc       |
+| gizmosphere/gizmo2            | AMD_FAMILY16_KB        | 2014-12-09 | eval      |
+| gizmosphere/gizmo             | AMD_FAMILY14           | 2014-01-03 | half      |
+| hp/abm                        | AMD_FAMILY16_KB        | 2015-01-05 | mini      |
+| hp/pavilion_m6_1035dx         | AMD_FAMILY15_TN        | 2014-03-28 | laptop    |
+| jetway/nf81-t56n-lf           | AMD_FAMILY14           | 2014-02-16 | mini      |
+| lenovo/g505s                  | AMD_FAMILY15_TN        | 2014-11-27 | laptop    |
+| lippert/frontrunner-af        | AMD_FAMILY14           | 2013-03-02 | half      |
+| msi/ms7721                    | AMD_FAMILY15_TN        | 2016-11-22 | desktop   |
+| pcengines/apu1                | AMD_FAMILY14           | 2015-02-23 | half      |
++-------------------------------+------------------------+------------+-----------+
+```
+
+
+## [4.17 Release](coreboot-4.17-relnotes.md)
+No Branch or builder
+
+* No platforms maintained on this release
+
+
 ## [4.16 Release](coreboot-4.16-relnotes.md)
 Branch created, builder configured