Documentation: perf: Indent filter options list of hisi-pcie-pmu

Documentation: perf: Indent filter options list of hisi-pcie-pmu

The "Filter options" list have a rather ugly indentation. Also, the first
paragraph after list name is rendered without separator (as continuation
from the name).

Align the list by indenting the list items and add a blank line
separator for each list name.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20221117084136.53572-4-yangyicong@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>