Add my previous gpg key fingerprint

Due to a change of employer I stopped using this key, but since it
was used to sign several Gerrit releases it should be listed here.

The key is not expired, so note it as "obsoleted" instead.

Change-Id: Ic9cf065044c98d790005f42d7d77fead9c201f4b
diff --git a/releases/public-keys.md b/releases/public-keys.md
index a6401c0..27b474b 100644
--- a/releases/public-keys.md
+++ b/releases/public-keys.md
@@ -3,10 +3,11 @@
 The following public keys are used to sign release artifacts that
 are deployed to Maven Central:
 
-| Name             | Email Address          | Fingerprint                                        |
-|------------------|------------------------|----------------------------------------------------|
-| David Pursehouse | dpursehouse@collab.net | 0A76 9EB0 5339 B93B DD89  95ED 0C3A F664 9FFC 2102 |
-| Edwin Kempin     | ekempin@google.com     | 8DC3 89F5 9066 40FA C5A9  9037 51B5 FD97 A0D0 EF51 |
-| Saša Živkov      | sasa.zivkov@sap.com    | 024B 9991 1E26 0764 22A7  5AD4 4D52 61F9 26C1 290E |
+| Name             | Email Address                   | Fingerprint                                        | Notes     |
+|------------------|---------------------------------|----------------------------------------------------|-----------|
+| David Pursehouse | dpursehouse@collab.net          | 0A76 9EB0 5339 B93B DD89  95ED 0C3A F664 9FFC 2102 |           |
+|                  | david.pursehouse@sonymobile.com | 5BEE 1865 DB05 5B31 9DCB  1369 F236 A953 E082 5A6D | Obsoleted |
+| Edwin Kempin     | ekempin@google.com              | 8DC3 89F5 9066 40FA C5A9  9037 51B5 FD97 A0D0 EF51 |           |
+| Saša Živkov      | sasa.zivkov@sap.com             | 024B 9991 1E26 0764 22A7  5AD4 4D52 61F9 26C1 290E |           |
 
 These keys are available on the [Ubuntu Public Key Server](https://keyserver.ubuntu.com/).