MAINTAINERS: arm: samsung: add Git tree and IRC

Add already used Krzysztof Kozlowski's Git tree for Samsung
S3C/S5P/Exynos ARM sub-architecture and IRC channel (#linux-exynos at
Libera).  This documents purely existing state.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220207175503.425200-1-krzysztof.kozlowski@canonical.com'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

MAINTAINERS

@@ -2575,7 +2575,9 @@ R:	Alim Akhtar <alim.akhtar@samsung.com>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 L:	linux-samsung-soc@vger.kernel.org
 S:	Maintained
+C:	irc://irc.libera.chat/linux-exynos
 Q:	https://patchwork.kernel.org/project/linux-samsung-soc/list/
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux.git
 F:	Documentation/arm/samsung/
 F:	Documentation/devicetree/bindings/arm/samsung/
 F:	Documentation/devicetree/bindings/power/pd-samsung.yaml
@@ -15296,6 +15298,7 @@ R:	Alim Akhtar <alim.akhtar@samsung.com>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 L:	linux-samsung-soc@vger.kernel.org
 S:	Maintained
+C:	irc://irc.libera.chat/linux-exynos
 Q:	https://patchwork.kernel.org/project/linux-samsung-soc/list/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/pinctrl/samsung.git
 F:	Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt