Remove numerous things deprecated during the 0.14 release cycle

Basically everything that has a direct replacement or no uses left.

Notable omissions:

- std.ArrayHashMap: Too much fallout, needs a separate cleanup.
- std.debug.runtime_safety: Too much fallout.
- std.heap.GeneralPurposeAllocator: Lots of references to it remain, not
  a simple find and replace as "debug allocator" is not equivalent to
  "general purpose allocator".
- std.io.Reader: Is being reworked at the moment.
- std.unicode.utf8Decode(): No replacement, needs a new API first.
- Manifest backwards compat options: Removal would break test data used
  by TestFetchBuilder.
- panic handler needs to be a namespace: Many tests still rely on it
  being a function, needs a separate cleanup.

1 files changed, 0 insertions, 2 deletions

diff --git a/lib/std/atomic.zig b/lib/std/atomic.zig
index 4ff8f0c3b9..194f645975 100644
--- a/lib/std/atomic.zig
+++ b/lib/std/atomic.zig
@@ -10,8 +10,6 @@ pub fn Value(comptime T: type) type {
             return .{ .raw = value };
         }
 
-        pub const fence = @compileError("@fence is deprecated, use other atomics to establish ordering");
-
         pub inline fn load(self: *const Self, comptime order: AtomicOrder) T {
             return @atomicLoad(T, &self.raw, order);
         }