mailmap: add address mapping for Jiri Kosina

Since I switched the MAINTAINERS entry to @kernel.org some time
ago, let's canonicalize my addressess to it.
Signed-off-by: Jiri Kosina <jikos@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

.mailmap

@@ -263,6 +263,9 @@ Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
 Jernej Skrabec <jernej.skrabec@gmail.com> <jernej.skrabec@siol.net>
 Jessica Zhang <quic_jesszhan@quicinc.com> <jesszhan@codeaurora.org>
 Jilai Wang <quic_jilaiw@quicinc.com> <jilaiw@codeaurora.org>
+Jiri Kosina <jikos@kernel.org> <jikos@jikos.cz>
+Jiri Kosina <jikos@kernel.org> <jkosina@suse.cz>
+Jiri Kosina <jikos@kernel.org> <jkosina@suse.com>
 Jiri Pirko <jiri@resnulli.us> <jiri@nvidia.com>
 Jiri Pirko <jiri@resnulli.us> <jiri@mellanox.com>
 Jiri Pirko <jiri@resnulli.us> <jpirko@redhat.com>