Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items

This commit adds frequency and num_overflows items to counter ABI file
(e.g. for TI ECAP hardware used in capture operating mode).
Signed-off-by: Julien Panis <jpanis@baylibre.com>
Link: https://lore.kernel.org/r/20220923142437.271328-3-jpanis@baylibre.com/Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/467ae80e97c586c6bc9c453c6156ffcb5d4853d6.1664318353.git.william.gray@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/ABI/testing/sysfs-bus-counter

@@ -209,6 +209,12 @@ Description:
 		both edges:
 			Any state transition.
 
+What:		/sys/bus/counter/devices/counterX/countY/num_overflows
+KernelVersion:	6.1
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This attribute indicates the number of overflows of count Y.
+
 What:		/sys/bus/counter/devices/counterX/countY/capture_component_id
 What:		/sys/bus/counter/devices/counterX/countY/ceiling_component_id
 What:		/sys/bus/counter/devices/counterX/countY/floor_component_id
@@ -220,12 +226,14 @@ What:		/sys/bus/counter/devices/counterX/countY/prescaler_component_id
 What:		/sys/bus/counter/devices/counterX/countY/preset_component_id
 What:		/sys/bus/counter/devices/counterX/countY/preset_enable_component_id
 What:		/sys/bus/counter/devices/counterX/countY/signalZ_action_component_id
+What:		/sys/bus/counter/devices/counterX/countY/num_overflows_component_id
 What:		/sys/bus/counter/devices/counterX/signalY/cable_fault_component_id
 What:		/sys/bus/counter/devices/counterX/signalY/cable_fault_enable_component_id
 What:		/sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler_component_id
 What:		/sys/bus/counter/devices/counterX/signalY/index_polarity_component_id
 What:		/sys/bus/counter/devices/counterX/signalY/polarity_component_id
 What:		/sys/bus/counter/devices/counterX/signalY/synchronous_mode_component_id
+What:		/sys/bus/counter/devices/counterX/signalY/frequency_component_id
 KernelVersion:	5.16
 Contact:	linux-iio@vger.kernel.org
 Description:
@@ -366,3 +374,9 @@ Description:
 			via index_polarity. The index function (as enabled via
 			preset_enable) is performed synchronously with the
 			quadrature clock on the active level of the index input.
+
+What:		/sys/bus/counter/devices/counterX/signalY/frequency
+KernelVersion:	6.1
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Read-only attribute that indicates the signal Y frequency, in Hz.