staging: r8188eu: remove unnecessary initialization

The variable 'retsig' in odm_signal_scale_mapping() is set in the
function before it returns, so it is not needed to initialize it.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220911161949.11293-4-straube.linux@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/hal/odm_HWConfig.c

@@ -15,7 +15,7 @@ static u8 odm_QueryRxPwrPercentage(s8 AntPower)
 
 static s32 odm_signal_scale_mapping(struct odm_dm_struct *dm_odm, s32 currsig)
 {
-	s32 retsig = 0;
+	s32 retsig;
 
 	if (currsig >= 51 && currsig <= 100)
 		retsig = 100;