staging: rtl8188eu: add blank line after declarations

Added a blank line after declarations in
drivers/staging/rtl8188eu/core/rtw_security.c to fix a
checkpatch.pl warning
Signed-off-by: Rahul Gottipati <rahul.blr97@gmail.com>
Link: https://lore.kernel.org/r/20200715163152.GA10190@rahulg-ThinkPad-T450Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8188eu/core/rtw_security.c

@@ -840,6 +840,7 @@ static void next_key(u8 *key, int round)
 static void byte_sub(u8 *in, u8 *out)
 {
 	int i;
+
 	for (i = 0; i < 16; i++)
 		out[i] = sbox(in[i]);
 }