MAINTAINERS: Add entries for Siemens IPC modules

There are different IPC driver modules in the kernel that are actively
maintained by Siemens but not yet listed in the MAINTAINERS file.
Add the missing entries.
Signed-off-by: Gerd Haeussler <gerd.haeussler.ext@siemens.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230814073114.2885-1-haeussler.gerd@gmail.comReviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

MAINTAINERS

@@ -19390,6 +19390,32 @@ F:	drivers/media/mmc/siano/
 F:	drivers/media/usb/siano/
 F:	drivers/media/usb/siano/
 
+SIEMENS IPC LED DRIVERS
+M:	Gerd Haeussler <gerd.haeussler.ext@siemens.com>
+M:	Xing Tong Wu <xingtong.wu@siemens.com>
+M:	Tobias Schaffner <tobias.schaffner@siemens.com>
+L:	linux-leds@vger.kernel.org
+S:	Maintained
+F:	drivers/leds/simple/
+
+SIEMENS IPC PLATFORM DRIVERS
+M:	Gerd Haeussler <gerd.haeussler.ext@siemens.com>
+M:	Xing Tong Wu <xingtong.wu@siemens.com>
+M:	Tobias Schaffner <tobias.schaffner@siemens.com>
+L:	platform-driver-x86@vger.kernel.org
+S:	Maintained
+F:	drivers/platform/x86/siemens/
+F:	include/linux/platform_data/x86/simatic-ipc-base.h
+F:	include/linux/platform_data/x86/simatic-ipc.h
+
+SIEMENS IPC WATCHDOG DRIVERS
+M:	Gerd Haeussler <gerd.haeussler.ext@siemens.com>
+M:	Xing Tong Wu <xingtong.wu@siemens.com>
+M:	Tobias Schaffner <tobias.schaffner@siemens.com>
+L:	linux-watchdog@vger.kernel.org
+S:	Maintained
+F:	drivers/watchdog/simatic-ipc-wdt.c
+
 SIFIVE DRIVERS
 M:	Palmer Dabbelt <palmer@dabbelt.com>
 M:	Paul Walmsley <paul.walmsley@sifive.com>