[fix] : typo

Author: Hayao0819

default.conf

@@ -191,7 +191,8 @@ memtest86=true
 
 # Set the size of cowspace
 # Change the default behavior of "--cowspace"
-cowspace="1GB"
+# Example: 1G, 256M, 512M
+cowspace="1G"
 
 #-- language config --#