staging: rtl8188eu: simplify odm_evm_db_to_percentage()

Use clamp() to simplify code in odm_evm_db_to_percentage().
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/hal/odm_hwconfig.c

@@ -53,20 +53,11 @@ static s32 odm_signal_scale_mapping(struct odm_dm_struct *dm_odm, s32 currsig)
 static u8 odm_evm_db_to_percentage(s8 value)
 {
 	/*  -33dB~0dB to 0%~99% */
-	s8 ret_val;
-
-	ret_val = value;
-
-	if (ret_val >= 0)
-		ret_val = 0;
-	if (ret_val <= -33)
-		ret_val = -33;
-
-	ret_val = 0 - ret_val;
-	ret_val *= 3;
+	s8 ret_val = clamp(-value, 0, 33) * 3;
 
 	if (ret_val == 99)
 		ret_val = 100;
+
 	return ret_val;
 }