MAINTAINERS: Add include/hw/timer/tmu012.h to the SH4 R2D section

tmu012.h is the header that belongs to hw/timer/sh_timer.c, so we
should list it in the same section as sh_timer.c.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Message-ID: <20231026080011.156325-1-thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

MAINTAINERS

@@ -1617,6 +1617,7 @@ F: hw/intc/sh_intc.c
 F: hw/pci-host/sh_pci.c
 F: hw/timer/sh_timer.c
 F: include/hw/sh4/sh_intc.h
+F: include/hw/timer/tmu012.h
 
 Shix
 R: Yoshinori Sato <ysato@users.sourceforge.jp>