[NFC][compiler-rt][hwasan] Move hwasanThreadList().CreateCurrentThread() into InitThreads

[leonardchan]

Summary

Once D104553 lands, CreateCurrentThread will be able to accept optional parameters for initializing the hwasan thread object. On fuchsia, we can get stack info in the platform-specific InitThreads and pass it through CreateCurrentThread. On linux, this is a no-op.

compiler-rt/lib/hwasan/hwasan.cpp

static void InitInstrumentation() {
 
   if (!InitShadow()) {
     Printf("FATAL: HWAddressSanitizer cannot mmap the shadow memory.\n");
     DumpProcessMap();
     Die();
   }
 
   InitThreads();
-  hwasanThreadList().CreateCurrentThread();
 
   hwasan_instrumentation_inited = 1;
 }
 
 // Interface.
 
 uptr __hwasan_shadow_memory_dynamic_address;  // Global interface symbol.
 

compiler-rt/lib/hwasan/hwasan_linux.cpp

uptr thread_space_start =
       __hwasan_shadow_memory_dynamic_address - (1ULL << kShadowBaseAlignment);
   uptr thread_space_end =
       __hwasan_shadow_memory_dynamic_address - guard_page_size;
   ReserveShadowMemoryRange(thread_space_start, thread_space_end - 1,
                            "hwasan threads", /*madvise_shadow*/ false);
   ProtectGap(thread_space_end,
              __hwasan_shadow_memory_dynamic_address - thread_space_end);
   InitThreadList(thread_space_start, thread_space_end - thread_space_start);
+  hwasanThreadList().CreateCurrentThread();
 }
 
 bool MemIsApp(uptr p) {
 // Memory outside the alias range has non-zero tags.
 #  if !defined(HWASAN_ALIASING_MODE)
   CHECK(GetTagFromPointer(p) == 0);
 #  endif