cgen: panic with error message when go command fails (#10943)

vlib/builtin/builtin_nix.c.v

@@ -134,3 +134,11 @@ fn break_if_debugger_attached() {
 		_ = ptr
 	}
 }
+
+// These functions are Windows specific - provide dummys for *nix
+pub fn winapi_lasterr_str() string {
+	return ''
+}
+
+[noreturn]
+pub fn panic_lasterr() {}