arch: x86: add irq runtime statistics

Unlike tracing module mainly for debug usage, this is
to allow runtime profiling IRQ performance data, and
target to enable it in product release since platform
can choose to make it work with low weight protocol.

Enable this option and implement runtime_irq_stats()
in platform code, such as Intel ISH platform implement
with SHMI protocol to allow host profiling irq stats.

Signed-off-by: Qipeng Zha <qipeng.zha@intel.com>