perf/arm_dmc620: Fix hotplug callback leak in dmc620_pmu_init()

dmc620_pmu_init() won't remove the callback added by
cpuhp_setup_state_multi() when platform_driver_register() failed. Remove
the callback by cpuhp_remove_multi_state() in fail path.

Similar to the handling of arm_ccn_init() in commit 26242b33 ("bus:
arm-ccn: Prevent hotplug callback leak")

Fixes: 53c218da ("driver/perf: Add PMU driver for the ARM DMC-620 memory controller")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com>
Link: https://lore.kernel.org/r/20221115115540.6245-2-shangxiaojing@huawei.com


Signed-off-by: Will Deacon <will@kernel.org>