lib/cpumask: delete misleading comment

The comment says that HOTPLUG config option enables all cpus in
cpu_possible_mask up to NR_CPUs. This is wrong. Even if HOTPLUG is
enabled, the mask is populated on boot with respect to ACPI/DT records.
Signed-off-by: Yury Norov <yury.norov@gmail.com>

include/linux/cpumask.h

@@ -72,10 +72,6 @@ static inline void set_nr_cpu_ids(unsigned int nr)
  *  cpu_online_mask is the dynamic subset of cpu_present_mask,
  *  indicating those CPUs available for scheduling.
  *
- *  If HOTPLUG is enabled, then cpu_possible_mask is forced to have
- *  all NR_CPUS bits set, otherwise it is just the set of CPUs that
- *  ACPI reports present at boot.
- *
  *  If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
  *  depending on what ACPI reports as currently plugged in, otherwise
  *  cpu_present_mask is just a copy of cpu_possible_mask.