ACPI: Adjust system_state check

To enable smp_processor_id() and might_sleep() debug checks earlier, it's
required to add system states between SYSTEM_BOOTING and SYSTEM_RUNNING.

Make the decision whether a pci root is hotplugged depend on SYSTEM_RUNNING
instead of !SYSTEM_BOOTING. It makes no sense to cover states greater than
SYSTEM_RUNNING as there are not hotplug events on reboot and poweroff.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/20170516184735.446455652@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>