Remove unneeded #include "aom_ports/bitops.h"

It was added in https://aomedia-review.googlesource.com/c/aom/+/173025
for the declaration of get_msb(). It should have been removed in
https://aomedia-review.googlesource.com/c/aom/+/200421.

Change-Id: I2891f8a19f086f000b9866e90d386a113d2dd70f

av1/common/entropymode.h

diff --git a/av1/common/entropymode.h b/av1/common/entropymode.h
index b507eb1..891ae5e 100644
--- a/av1/common/entropymode.h
+++ b/av1/common/entropymode.h
@@ -12,7 +12,6 @@
 #ifndef AOM_AV1_COMMON_ENTROPYMODE_H_
 #define AOM_AV1_COMMON_ENTROPYMODE_H_
 
-#include "aom_ports/bitops.h"
 #include "av1/common/entropy.h"
 #include "av1/common/entropymv.h"
 #include "av1/common/filter.h"