thermal/cpufreq_cooling: Remove structure member documentation

The structure member documentation refers to a member which does not
exist any more. Remove it.

Link: https://lore.kernel.org/all/[e-mail]/
Reported-by: kernel test robot <[e-mail]>
Closes: https://lore.kernel.org/oe-kbuild-all/[e-mail]/
Signed-off-by: Daniel Lezcano <[e-mail]>
Acked-by: Viresh Kumar <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
[ rjw: Minor changelog edits ]
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/thermal/cpufreq_cooling.c

···
  * @max_level: maximum cooling level. One less than total number of valid
  *	cpufreq frequencies.
  * @em: Reference on the Energy Model of the device
- * @cdev: thermal_cooling_device pointer to keep track of the
- *	registered cooling device.
  * @policy: cpufreq policy.
  * @cooling_ops: cpufreq callbacks to thermal cooling device ops
  * @idle_time: idle time stats