tty: fix spelling mistake

Fix typo: "tigger" --> "trigger"

Signed-off-by: Flavio Suligoi <f.suligoi@asem.it>
Link: https://lore.kernel.org/r/20200609160249.31329-1-f.suligoi@asem.it
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/moxa.h

@@ -138,7 +138,7 @@
 #define IntrQuit	0x40	/* received QUIT code             */
 #define IntrEOF 	0x80	/* received EOF code              */
 
-#define IntrRxTrigger 	0x100	/* rx data count reach tigger value */
+#define IntrRxTrigger 	0x100	/* rx data count reach trigger value */
 #define IntrTxTrigger 	0x200	/* tx data count below trigger value */
 
 #define Magic_no	(Config_base + 0)