params: make parameter units more consistent (#15502)

src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c

@@ -592,7 +592,7 @@ PARAM_DEFINE_FLOAT(FW_T_INTEG_GAIN, 0.1f);
  * allows for reasonably aggressive pitch changes if required to recover
  * from under-speed conditions.
  *
- * @unit m/s/s
+ * @unit m/s^2
  * @min 1.0
  * @max 10.0
  * @decimal 1

src/modules/fw_pos_control_l1/launchdetection/launchdetection_params.c

@@ -57,7 +57,7 @@ PARAM_DEFINE_INT32(LAUN_ALL_ON, 0);
  *
  * LAUN_CAT_A for LAUN_CAT_T serves as threshold to trigger launch detection.
  *
- * @unit m/s/s
+ * @unit m/s^2
  * @min 0
  * @decimal 1
  * @increment 0.5