improve attr (#2945)

packages/a/attr/xmake.lua

@@ -4,16 +4,14 @@ package("attr")
     set_description("Commands for Manipulating Filesystem Extended Attributes")
     set_license("GPL-2.0")
 
-    add_urls("http://download.savannah.nongnu.org/releases/attr/attr-$(version).tar.gz")
+    add_urls("https://github.com/xmake-mirror/attr/releases/download/v$(version)/attr-$(version).tar.gz",
+             "http://download.savannah.nongnu.org/releases/attr/attr-$(version).tar.gz")
     add_versions("2.5.1", "bae1c6949b258a0d68001367ce0c741cebdacdd3b62965d17e5eb23cd78adaf8")
 
     on_install("linux", function (package)
         local configs = {}
         table.insert(configs, "--enable-shared=" .. (package:config("shared") and "yes" or "no"))
         table.insert(configs, "--enable-static=" .. (package:config("shared") and "no" or "yes"))
-        if package:config("pic") ~= false then
-            table.insert(configs, "--with-pic")
-        end
         import("package.tools.autoconf").install(package, configs)
     end)