MIPS: Malta: Allow use of MIPS CPS SMP implementation

This patch simply attempts to register the MIPS Coherent Processing
System SMP implementation when it is enabled. If registering that fails
for some reason (like the Kconfig option being disabled or a lack of
hardware support) then we fall back to the same SMP implementations as
before.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6365/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/Kconfig

@@ -329,6 +329,7 @@ config MIPS_MALTA
 	select SYS_SUPPORTS_BIG_ENDIAN
 	select SYS_SUPPORTS_LITTLE_ENDIAN
 	select SYS_SUPPORTS_MIPS_CMP
+	select SYS_SUPPORTS_MIPS_CPS
 	select SYS_SUPPORTS_MULTITHREADING
 	select SYS_SUPPORTS_SMARTMIPS
 	select SYS_SUPPORTS_ZBOOT

arch/mips/mti-malta/malta-init.c

@@ -285,6 +285,8 @@ mips_pci_controller:
 	mips_cm_probe();
 	mips_cpc_probe();
 
+	if (!register_cps_smp_ops())
+		return;
 	if (!register_cmp_smp_ops())
 		return;
 	if (!register_vsmp_smp_ops())