Auto merge of #254 - alexcrichton:rtld-default, r=alexcrichton

Add RTLD_DEFAULT to more platforms

Author: bors

src/unix/bsd/mod.rs

@@ -290,6 +290,7 @@ pub const NOFLSH: ::tcflag_t = 0x80000000;
 pub const WNOHANG: ::c_int = 1;
 
 pub const RTLD_NOW: ::c_int = 0x2;
+pub const RTLD_DEFAULT: *mut ::c_void = -2isize as *mut ::c_void;
 
 f! {
     pub fn FD_CLR(fd: ::c_int, set: *mut fd_set) -> () {

src/unix/notbsd/android/mod.rs

@@ -550,6 +550,7 @@ pub const TIOCCONS: ::c_int = 0x541D;
 pub const RTLD_GLOBAL: ::c_int = 0x2;
 pub const RTLD_NOLOAD: ::c_int = 0x4;
 pub const RTLD_NOW: ::c_int = 0;
+pub const RTLD_DEFAULT: *mut ::c_void = -1isize as *mut ::c_void;
 
 f! {
     pub fn sigemptyset(set: *mut sigset_t) -> ::c_int {