Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/Documentation/input/rotary-encoder.txt b/Documentation/input/rotary-encoder.txt
index 8b4129d..943e8f6 100644
--- a/Documentation/input/rotary-encoder.txt
+++ b/Documentation/input/rotary-encoder.txt
@@ -46,7 +46,7 @@
 
 d) Falling edge on channel B, channel A in low state
 	Parking position. If the encoder enters this state, a full transition
-	should have happend, unless it flipped back on half the way. The
+	should have happened, unless it flipped back on half the way. The
 	'armed' state tells us about that.
 
 2. Platform requirements