arm: perf: use builtin_platform_driver

Use builtin_platform_driver() helper to simplify the code.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm/kernel/perf_event_v6.c

@@ -581,9 +581,5 @@ static struct platform_driver armv6_pmu_driver = {
 	.probe		= armv6_pmu_device_probe,
 };
 
-static int __init register_armv6_pmu_driver(void)
-{
-	return platform_driver_register(&armv6_pmu_driver);
-}
-device_initcall(register_armv6_pmu_driver);
+builtin_platform_driver(armv6_pmu_driver);
 #endif	/* CONFIG_CPU_V6 || CONFIG_CPU_V6K */

arch/arm/kernel/perf_event_v7.c

@@ -2034,9 +2034,5 @@ static struct platform_driver armv7_pmu_driver = {
 	.probe		= armv7_pmu_device_probe,
 };
 
-static int __init register_armv7_pmu_driver(void)
-{
-	return platform_driver_register(&armv7_pmu_driver);
-}
-device_initcall(register_armv7_pmu_driver);
+builtin_platform_driver(armv7_pmu_driver);
 #endif	/* CONFIG_CPU_V7 */

arch/arm/kernel/perf_event_xscale.c

@@ -767,9 +767,5 @@ static struct platform_driver xscale_pmu_driver = {
 	.probe		= xscale_pmu_device_probe,
 };
 
-static int __init register_xscale_pmu_driver(void)
-{
-	return platform_driver_register(&xscale_pmu_driver);
-}
-device_initcall(register_xscale_pmu_driver);
+builtin_platform_driver(xscale_pmu_driver);
 #endif	/* CONFIG_CPU_XSCALE */