sensor-hal: tm1: check "enable" attribute instead of "poll_delay" in TM1

sensor-hal: tm1: check "enable" attribute instead of "poll_delay" in TM1

Specially, input device driver of proximity sensor in tm1 doesn't have poll_delay
attribute(device node). other devices(tw1, emulator) don't have this
problem.

* only the sensor input devices have "enable" node as you can see the following.
sh-3.2# ls -al /sys/class/input/input*/enable
-rw-rw-r-- 1 sensor input 4096 Jul 26 04:49 /sys/class/input/input4/enable
-rw-rw-r-- 1 sensor input 4096 Jul 26 04:49 /sys/class/input/input5/enable

Change-Id: Ie11f89caf24203b8899987cfc9e42e2706d17f34
Signed-off-by: kibak.yoon <kibak.yoon@samsung.com>