ACPI: processor: idle: Drop extra prefix from pr_notice()

Drop "ACPI: " from the pr_noitice() instance in
acpi_processor_cstate_first_run_checks(), because pr_fmt() causes
that prefix to be added to the message already.

Reported-by: Hanjun Guo <[e-mail]>
Signed-off-by: Rafael J. Wysocki <[e-mail]>
Reviewed-by: Hanjun Guo <[e-mail]>

drivers/acpi/processor_idle.c

···
 	dmi_check_system(processor_power_dmi_table);
 	max_cstate = acpi_processor_cstate_check(max_cstate);
 	if (max_cstate < ACPI_C_STATES_MAX)
-		pr_notice("ACPI: processor limited to max C-state %d\n",
-			  max_cstate);
+		pr_notice("processor limited to max C-state %d\n", max_cstate);
+
 	first_run++;
 
 	if (nocst)