AC_AttitudeControl: reduce alt hold min lean angle to 5deg on plane

libraries/AC_AttitudeControl/AC_AttitudeControl.cpp

@@ -6,9 +6,11 @@ extern const AP_HAL::HAL& hal;
 #if APM_BUILD_TYPE(APM_BUILD_ArduPlane)
  // default gains for Plane
  # define AC_ATTITUDE_CONTROL_INPUT_TC_DEFAULT  0.2f    // Soft
+ #define AC_ATTITUDE_CONTROL_ANGLE_LIMIT_MIN     5.0     // Min lean angle so that vehicle can maintain limited control
 #else
  // default gains for Copter and Sub
  # define AC_ATTITUDE_CONTROL_INPUT_TC_DEFAULT  0.15f   // Medium
+ #define AC_ATTITUDE_CONTROL_ANGLE_LIMIT_MIN     10.0   // Min lean angle so that vehicle can maintain limited control
 #endif
 
 AC_AttitudeControl *AC_AttitudeControl::_singleton;

libraries/AC_AttitudeControl/AC_AttitudeControl.h

@@ -35,7 +35,6 @@
 
 #define AC_ATTITUDE_CONTROL_ANGLE_LIMIT_TC_DEFAULT      1.0f    // Time constant used to limit lean angle so that vehicle does not lose altitude
 #define AC_ATTITUDE_CONTROL_ANGLE_LIMIT_THROTTLE_MAX    0.8f    // Max throttle used to limit lean angle so that vehicle does not lose altitude
-#define AC_ATTITUDE_CONTROL_ANGLE_LIMIT_MIN             10.0f   // Min lean angle so that vehicle can maintain limited control
 
 #define AC_ATTITUDE_CONTROL_MIN_DEFAULT                 0.1f    // minimum throttle mix default
 #define AC_ATTITUDE_CONTROL_MAN_DEFAULT                 0.1f    // manual throttle mix default