Input: i8042 - disable interfaces when switching to legacy mode

Disable both keyboard and auxiliary interfaces before switching
to legacy mode to prevent atkbd from getting "empty" interrupts.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c
index ec195a3..ff40b5c 100644
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -762,6 +762,13 @@
 	i8042_flush();
 
 /*
+ * Disable both KBD and AUX interfaces so they don't get in the way
+ */
+
+	i8042_ctr |= I8042_CTR_KBDDIS | I8042_CTR_AUXDIS;
+	i8042_ctr &= ~(I8042_CTR_KBDINT | I8042_CTR_AUXINT);
+
+/*
  * Disable MUX mode if present.
  */