This commit refactors ks_wlan_set_rx_gain function to
improve readability:
    - error condition is handling the error to avoid an 'else'
    - ternary operator is used to clean if-else block assignment.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
        if (priv->sleep_mode == SLP_SLEEP)
                return -EPERM;
        /* for SLEEP MODE */
-       if (*uwrq >= 0 && *uwrq <= 0xFF)        /* 0-255 */
-               priv->gain.tx_gain = (uint8_t)*uwrq;
-       else
+       if (*uwrq < 0 || *uwrq > 0xFF)
                return -EINVAL;
 
-       if (priv->gain.tx_gain < 0xFF)
-               priv->gain.tx_mode = 1;
-       else
-               priv->gain.tx_mode = 0;
-
+       priv->gain.tx_gain = (uint8_t)*uwrq;
+       priv->gain.tx_mode = (priv->gain.tx_gain < 0xFF) ? 1 : 0;
        hostif_sme_enqueue(priv, SME_SET_GAIN);
        return 0;
 }