soc: renesas: Enable TMU support on R-Car Gen2

All Renesas R-Car Gen2 SoCs have Timer Units (TMU).  Enable support for
them by selecting the SYS_SUPPORTS_SH_TMU gatekeeper config symbol.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/b7b9fdd6f517a8b29bf5754e7f083d3b71805130.1710865761.git.geert+renesas@glider.be

drivers/soc/renesas/Kconfig

@@ -24,6 +24,7 @@ config ARCH_RCAR_GEN2
 	select RENESAS_IRQC
 	select RST_RCAR
 	select SYS_SUPPORTS_SH_CMT
+	select SYS_SUPPORTS_SH_TMU
 
 config ARCH_RCAR_GEN3
 	bool