AutoTest: reduce heli rate P values

Also remove explicit params to use EKF2 because it is used by default now

Tools/autotest/Helicopter.parm

@@ -35,12 +35,12 @@ INS_ACC3SCAL_Z   1.000
 RATE_PIT_D 0.0500
 RATE_PIT_I 12.5000
 RATE_PIT_IMAX 4500.0000
-RATE_PIT_P 5.0000
+RATE_PIT_P 1.0000
 RATE_PIT_VFF 0.220000
 RATE_RLL_D 0.0500
 RATE_RLL_I 12.5000
 RATE_RLL_IMAX 4500.0000
-RATE_RLL_P 5.0000
+RATE_RLL_P 1.0000
 RATE_RLL_VFF 0.220000
 RATE_YAW_D 0.0200
 RATE_YAW_I 0.0975
@@ -73,8 +73,6 @@ RC8_MAX         2000.000000
 RC8_MIN         1000.000000
 RC8_TRIM        1500.000000
 WP_YAW_BEHAVIOR 2
-EK2_ENABLE      1
-AHRS_EKF_TYPE   2
 IM_ACRO_COL_EXP 0.2
 IM_STAB_COL_1   400
 IM_STAB_COL_2   600