staging: rtl8192e: Change cpu_to_le16 to le16_to_cpu

Since the function auth_parse returns a u16, and
struct rtllib_authentication.status is defined as an __le16, it seems
that

	return cpu_to_le16(a->status);

should be

	return le16_to_cpu(a->status);

This change silences the following sparse warnings:
drivers/staging/rtl8192e/rtllib_softmac.c:1817:16:
 warning: cast from restricted __le16
drivers/staging/rtl8192e/rtllib_softmac.c:1817:16:
 warning: incorrect type in return expression (different base types)
drivers/staging/rtl8192e/rtllib_softmac.c:1817:16:
    expected unsigned short
drivers/staging/rtl8192e/rtllib_softmac.c:1817:16:
    got restricted __le16 [usertype] <noident>
Signed-off-by: Arno Tiemersma <arno.tiemersma@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8192e/rtllib_softmac.c

@@ -1814,7 +1814,7 @@ static inline u16 auth_parse(struct sk_buff *skb, u8 **challenge, int *chlen)
 				return -ENOMEM;
 		}
 	}
-	return cpu_to_le16(a->status);
+	return le16_to_cpu(a->status);
 }
 
 static int auth_rq_parse(struct sk_buff *skb, u8 *dest)