Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/sound/soc/codecs/wm8991.c b/sound/soc/codecs/wm8991.c
index 28fdfd6..3c2ee1b 100644
--- a/sound/soc/codecs/wm8991.c
+++ b/sound/soc/codecs/wm8991.c
@@ -981,7 +981,7 @@
 		reg = snd_soc_read(codec, WM8991_CLOCKING_2);
 		snd_soc_write(codec, WM8991_CLOCKING_2, reg | WM8991_SYSCLK_SRC);
 
-		/* set up N , fractional mode and pre-divisor if neccessary */
+		/* set up N , fractional mode and pre-divisor if necessary */
 		snd_soc_write(codec, WM8991_PLL1, pll_div.n | WM8991_SDM |
 			      (pll_div.div2 ? WM8991_PRESCALE : 0));
 		snd_soc_write(codec, WM8991_PLL2, (u8)(pll_div.k>>8));