Revert "powerpc/topology: Update topology_core_cpumask"

Now that cpu_core_mask has been reintroduced, lets revert
commit 4bce5459 ("powerpc/topology: Update topology_core_cpumask")

Post this commit, lscpu should reflect topologies as requested by a user
when a QEMU instance is launched with NUMA spanning multiple sockets.
Reported-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210415120934.232271-3-srikar@linux.vnet.ibm.com

arch/powerpc/include/asm/topology.h

@@ -126,7 +126,7 @@ static inline int cpu_to_coregroup_id(int cpu)
 #define topology_physical_package_id(cpu)	(cpu_to_chip_id(cpu))
 
 #define topology_sibling_cpumask(cpu)	(per_cpu(cpu_sibling_map, cpu))
-#define topology_core_cpumask(cpu)	(cpu_cpu_mask(cpu))
+#define topology_core_cpumask(cpu)	(per_cpu(cpu_core_map, cpu))
 #define topology_core_id(cpu)		(cpu_to_core_id(cpu))
 
 #endif