Revert "Updated minimal/chipflow.toml"

This reverts commit 53c17cc.

Author: robtaylor

minimal/chipflow.toml

@@ -9,10 +9,7 @@ board = "design.steps.board:MyBoardStep"
 software = "design.steps.software:MySoftwareStep"
 
 [chipflow.silicon]
-process = "ihp_sg13g2"
-package = "pga144"
+process = "sky130"
+package = "openframe"
+
 
-[chipflow.silicon.pads]
-# System
-sys_clk   = { type = "clock", loc = "114" }
-sys_rst_n = { type = "reset", loc = "115" }