common: Drop linux/bitops.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/usb/eth/lan75xx.c b/drivers/usb/eth/lan75xx.c
index 94c6522..46b92e8 100644
--- a/drivers/usb/eth/lan75xx.c
+++ b/drivers/usb/eth/lan75xx.c
@@ -6,6 +6,7 @@
 #include <dm.h>
 #include <log.h>
 #include <usb.h>
+#include <linux/bitops.h>
 #include <linux/mii.h>
 #include "usb_ether.h"
 #include "lan7x.h"