eliminate os_core, move into base; eliminate regs, move into arch abstraction layer, define x64 regs in x64 layer; move win32 backend for os core (now base) functionality to top-level win32 layer

src/base/base_markup.c

@@ -1,21 +1,2 @@
 // Copyright (c) Epic Games Tools
 // Licensed under the MIT license (https://opensource.org/license/mit/)
-
-internal void
-set_thread_name(String8 string)
-{
-  ProfThreadName("%.*s", str8_varg(string));
-  os_set_thread_name(string);
-}
-
-internal void
-set_thread_namef(char *fmt, ...)
-{
-  Temp scratch = scratch_begin(0, 0);
-  va_list args;
-  va_start(args, fmt);
-  String8 string = push_str8fv(scratch.arena, fmt, args);
-  set_thread_name(string);
-  va_end(args);
-  scratch_end(scratch);
-}