Update help message

README.md

@@ -3,7 +3,7 @@
 This is a script to control 4-pin PWM fans on ASRock Rack motherboards with IPMI. The BMC does not properly expose fan control, so they must be controlled using raw IPMI commands. This script is a user-friendly way to do that.
 
 
-    usage: asrock-pwm-ipmi [-h] [-i] [-a] [FAN:SPEED [FAN:SPEED ...]]
+    usage: asrock-pwm-ipmi [-h] [-i] [-a] [-q] [FAN:SPEED [FAN:SPEED ...]]
 
     Read information about and control fans on ASRock boards with IPMI.
 
@@ -15,3 +15,5 @@ This is a script to control 4-pin PWM fans on ASRock Rack motherboards with IPMI
       -h, --help  show this help message and exit
       -i, --info  Read fan information
       -a, --auto  Service to control fans based on temperature
+      -q, --quiet  Hide output
+