Fix undefined behavior of left shift

Left shifting UCHAR promotes it to a signed integer. When the
value is >= 128 and shifted by 24, the result sets the sign bit,
causing undefined behavior. Fixes it by explicit casting to UINT.

src/Mayaqua/Encrypt.c

@@ -4761,7 +4761,7 @@ static void MY_SHA0_Transform(MY_SHA0_CTX* ctx) {
 	UCHAR* p = ctx->buf;
 	int t;
 	for(t = 0; t < 16; ++t) {
-		UINT tmp =  *p++ << 24;
+		UINT tmp =  (UINT)*p++ << 24;
 		tmp |= *p++ << 16;
 		tmp |= *p++ << 8;
 		tmp |= *p++;