all: move mach.Timer, core Timer/Frequency to mach.time module

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

src/time/main.zig

@@ -0,0 +1,11 @@
+pub const std = @import("std");
+
+pub const ns_per_s = std.time.ns_per_s;
+
+pub const Timer = @import("Timer.zig");
+pub const Frequency = @import("Frequency.zig");
+
+test {
+    _ = Timer;
+    _ = Frequency;
+}