include: kernel: Fix use of K_POLL_MODE_INFORM_ONLY in docstring
include: kernel: Fix use of K_POLL_MODE_INFORM_ONLY in docstring

K_POLL_MODE_INFORM_ONLY was renamed to K_POLL_MODE_NOTIFY_ONLY, but
stale use was in a docstring.

Signed-off-by: Paul Sokolovsky <35cb557f011771c94f127d6fef99f804b62203f5@linaro.org>

ldts/zephyr,zephyriot/zephyr,GiulianoFranchetto/zephyr,aceofall/zephyr-iotos,zephyrproject-rtos/zephyr,aceofall/zephyr-iotos,fbsder/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,nashif/zephyr,rsalveti/zephyr,Vudentz/zephyr,kraj/zephyr,finikorg/zephyr,mbolivar/zephyr,nashif/zephyr,kraj/zephyr,ldts/zephyr,runchip/zephyr-cc3220,mbolivar/zephyr,galak/zephyr,explora26/zephyr,explora26/zephyr,zephyrproject-rtos/zephyr,zephyriot/zephyr,rsalveti/zephyr,aceofall/zephyr-iotos,fbsder/zephyr,rsalveti/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,ldts/zephyr,zephyriot/zephyr,galak/zephyr,kraj/zephyr,mbolivar/zephyr,runchip/zephyr-cc3220,finikorg/zephyr,runchip/zephyr-cc3220,punitvara/zephyr,mbolivar/zephyr,zephyriot/zephyr,rsalveti/zephyr,punitvara/zephyr,kraj/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,fbsder/zephyr,fbsder/zephyr,explora26/zephyr,aceofall/zephyr-iotos,finikorg/zephyr,nashif/zephyr,zephyriot/zephyr,galak/zephyr,nashif/zephyr,Vudentz/zephyr,aceofall/zephyr-iotos,ldts/zephyr,runchip/zephyr-cc3220,kraj/zephyr,punitvara/zephyr,ldts/zephyr,fbsder/zephyr,rsalveti/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,runchip/zephyr-cc3220,punitvara/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,Vudentz/zephyr,Vudentz/zephyr,Vudentz/zephyr,galak/zephyr,mbolivar/zephyr,nashif/zephyr,finikorg/zephyr