ANDROID: GKI: add thermal_zone_get_slope() to the .xml file

This came in through the android11-5.4 lts branch, so we need to track
it here as well:

Leaf changes summary: 1 artifact changed
Changed leaf types summary: 0 leaf type changed
Removed/Changed/Added functions summary: 0 Removed, 0 Changed, 1 Added function
Removed/Changed/Added variables summary: 0 Removed, 0 Changed, 0 Added variable

1 Added function:

  [A] 'function int thermal_zone_get_slope(thermal_zone_device*)'

Bug: 146449535
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I34acbc780a94d58b70c13af3469d90dc8c39b955