counter: Introduce the Count capture component

Some devices provide a latch function to save historic Count values.
This patch standardizes exposure of such functionality as Count capture
components. A COUNTER_COMP_CAPTURE macro is provided for driver authors
to define a capture component. A new event COUNTER_EVENT_CAPTURE is
introduced to represent Count value capture events.

Cc: Julien Panis <jpanis@baylibre.com>
Link: https://lore.kernel.org/r/c239572ab4208d0d6728136e82a88ad464369a7a.1664204990.git.william.gray@linaro.org/


Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/3cebaa0b807a225eb277d771504fe6dba7269ffd.1664318353.git.william.gray@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>