veil: add package (#2428)

* veil: add package

* fix test

packages/v/veil/xmake.lua

@@ -0,0 +1,20 @@
+package("veil")
+    set_kind("library", {headeronly = true})
+    set_homepage("https://github.com/MiroKaku/Veil")
+    set_description("Windows internal undocumented API.")
+    set_license("MIT")
+
+    add_urls("https://github.com/MiroKaku/Veil.git")
+    add_versions("2023.07.19", "56464db15ebede014195ba82e2dc46d302c83798")
+
+    on_install("windows", function (package)
+        package:add("syslinks", "ntdll")
+        io.replace("Veil.h", "#pragma comment(lib, \"ntdll.lib\")", "", {plain = true})
+
+        os.cp("Veil", package:installdir("include"))
+        os.cp("veil.h", package:installdir("include"))
+    end)
+
+    on_test(function (package)
+        assert(package:has_cxxfuncs("NtReadFile", {includes = "veil.h"}))
+    end)