riscv: Kconfig: enable SCHED_MC kconfig

RISC-V now builds the sched domain based on the simple possible map.

Enable SCHED_MC to make the building based on cpu_coregroup_mask()
which also takes care of the NUMA and cores with LLC.
Signed-off-by: Song Shuai <suagrfillet@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230310110336.970985-1-suagrfillet@gmail.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/Kconfig

@@ -322,6 +322,14 @@ config SMP
 
 	  If you don't know what to do here, say N.
 
+config SCHED_MC
+	bool "Multi-core scheduler support"
+	depends on SMP
+	help
+	  Multi-core scheduler support improves the CPU scheduler's decision
+	  making when dealing with multi-core CPU chips at a cost of slightly
+	  increased overhead in some places. If unsure say N here.
+
 config NR_CPUS
 	int "Maximum number of CPUs (2-512)"
 	depends on SMP