Apply deprecation to linux uses of RLIM_NLIMITS

The deprecation for RLIM_NLIMITS was unintentionally removed in
ad3f860.

Author: androm3da

src/unix/linux_like/android/mod.rs

@@ -1559,6 +1559,7 @@ pub const RLIMIT_MSGQUEUE: ::c_int = 12;
 pub const RLIMIT_NICE: ::c_int = 13;
 pub const RLIMIT_RTPRIO: ::c_int = 14;
 
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = 16;
 pub const RLIM_INFINITY: ::rlim_t = !0;
 

src/unix/linux_like/linux/arch/generic/mod.rs

@@ -277,16 +277,19 @@ cfg_if! {
         pub const RLIMIT_NICE: ::c_int = 13;
         pub const RLIMIT_RTPRIO: ::c_int = 14;
         pub const RLIMIT_RTTIME: ::c_int = 15;
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::c_int = 15;
         pub const RLIMIT_NLIMITS: ::c_int = RLIM_NLIMITS;
     }
 }
 
 cfg_if! {
     if #[cfg(target_env = "gnu")] {
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 16;
     }
     else if #[cfg(target_env = "uclibc")] {
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 15;
     }
 }