Set default motor_max_speed_rpm to 75 again

Signed-off-by: Gregory Mermet <g.mermet@ez-wheel.com>

Author: GMezWheel

launch/swd_diff_drive_controller.launch

@@ -9,7 +9,7 @@
   <arg name="control_mode" default="Twist" />
   <arg name="base_frame" default="base_link" />
   <arg name="odom_frame" default="odom" />
-  <arg name="wheel_max_speed_rpm" default="95" />
+  <arg name="wheel_max_speed_rpm" default="75" />
   <arg name="wheel_safety_limited_speed_rpm" default="40" />
   <arg name="have_backward_sls" default="false" />
   <arg name="left_encoder_relative_error" default="0.2" />