example/KC705: Add example design for Xilinx KC705

Signed-off-by: Alex Forencich <alex@alexforencich.com>

example/KC705/fpga/fpga_gmii_1g/config.tcl

@@ -0,0 +1,26 @@
+# SPDX-License-Identifier: MIT
+#
+# Copyright (c) 2025 FPGA Ninja, LLC
+#
+# Authors:
+# - Alex Forencich
+#
+
+set params [dict create]
+
+# Type of PHY on RJ-45 10/100/1000BASE-T port (GMII, RGMII, or SGMII)
+dict set params BASET_PHY_TYPE "GMII"
+
+# Invert polarity for SFP+ cage
+# KC705 rev 1.0: diff pairs to SFP+ are polarity-swapped
+dict set params SFP_INVERT "1"
+# KC705 rev 1.1: diff pairs to SFP+ are correct
+#dict set params SFP_INVERT "0"
+
+# apply parameters to top-level
+set param_list {}
+dict for {name value} $params {
+    lappend param_list $name=$value
+}
+
+set_property generic $param_list [get_filesets sources_1]