Revert "param MPC_MAN_TILT_MAX: decrease maximum from 90 to 85 degrees"

This reverts commit d6df692b.

The changes to attitude controller improve this a lot.

src/modules/mc_pos_control/mc_pos_control_params.c

@@ -341,7 +341,7 @@ PARAM_DEFINE_FLOAT(MPC_TKO_SPEED, 1.5f);
  *
  * @unit deg
  * @min 0.0
- * @max 85.0
+ * @max 90.0
  * @decimal 1
  * @group Multicopter Position Control
  */