sh: fix function signature of cpu_coregroup_mask to match pointer type

The signedness mismatch of the argument type produces an error
compiling kernel/sched/core.c with -Werror=incompatible-pointer-types,
which is now used by default.

Fixes: ea8daa7b9784 "kbuild: Add option to turn incompatible pointer check into error"
Signed-off-by: Rich Felker <dalias@libc.org>

arch/sh/include/asm/topology.h

@@ -17,7 +17,7 @@
 
 #define mc_capable()    (1)
 
-const struct cpumask *cpu_coregroup_mask(unsigned int cpu);
+const struct cpumask *cpu_coregroup_mask(int cpu);
 
 extern cpumask_t cpu_core_map[NR_CPUS];
 

arch/sh/kernel/topology.c

@@ -21,7 +21,7 @@ static DEFINE_PER_CPU(struct cpu, cpu_devices);
 cpumask_t cpu_core_map[NR_CPUS];
 EXPORT_SYMBOL(cpu_core_map);
 
-static cpumask_t cpu_coregroup_map(unsigned int cpu)
+static cpumask_t cpu_coregroup_map(int cpu)
 {
 	/*
 	 * Presently all SH-X3 SMP cores are multi-cores, so just keep it
@@ -30,7 +30,7 @@ static cpumask_t cpu_coregroup_map(unsigned int cpu)
 	return *cpu_possible_mask;
 }
 
-const struct cpumask *cpu_coregroup_mask(unsigned int cpu)
+const struct cpumask *cpu_coregroup_mask(int cpu)
 {
 	return &cpu_core_map[cpu];
 }