gateware/firmware: Match rx/tx tick order in register with doc

The documentation always had the rRX tick in the LSB which
is consistent with having the RX units before TX.

They can be read as 16 bit value anyway so there isn't any
performance impact.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
diff --git a/gateware/e1-tracer/rtl/misc.v b/gateware/e1-tracer/rtl/misc.v
index 99ae0b8..c64ad8b 100644
--- a/gateware/e1-tracer/rtl/misc.v
+++ b/gateware/e1-tracer/rtl/misc.v
@@ -76,8 +76,8 @@
 			wb_rdata <= 32'h00000000;
 		else
 			case (wb_addr[3:0])
-				4'h4:    wb_rdata <= { cap_e1_rx[0], 16'h0000 };
-				4'h5:    wb_rdata <= { cap_e1_rx[1], 16'h0000 };
+				4'h4:    wb_rdata <= { 16'h000, cap_e1_rx[0] };
+				4'h5:    wb_rdata <= { 16'h000, cap_e1_rx[1] };
 				4'h7:    wb_rdata <= cnt_time;
 				default: wb_rdata <= 32'hxxxxxxxx;
 			endcase