Remove unecessary unsigned constant

Author: saxbophone

sxbp/serialisation.c

@@ -130,7 +130,7 @@ static void sxbp_write_sxbp_data_line(
 ) {
     size_t index = *start_index;
     // the leading 2 bits of the first byte are used for the direction
-    buffer->bytes[index] = line.direction << 6u;
+    buffer->bytes[index] = line.direction << 6;
     // the next 6 bits of the first byte are used for the first 6 bits of length
     buffer->bytes[index] |= (line.length >> 24);
     // move on to the next byte