ACPI / LPIT: Correct LPIT end address for lpit_process()

Correct the LPIT end address which is passed into lpit_process()
and the end address limit test in lpit_process().

The LPI state descriptor subtables follow the fixed sized
acpi_lpit_header up to the end of the LPIT. The last LPI state
descriptor can end at exactly the end of the LPIT.

Note that this is a fix to a latent problem. Although incorrect,
the unpatched version works because the passed in end address
is just slightly beyond the actual end of the LPIT and the size
of the ACPI LPIT header is smaller than the size of the only
currently defined LPI state descriptor, acpi_lpit_native.

Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>