Fix data race in jl_new_module__ (JuliaLang#58880)

Use an atomic fetch and add to fix a data race in `Module()` identified
by tsan:

```
./usr/bin/julia -t4,0 --gcthreads=1 -e 'Threads.@threads for i=1:100 Module() end'
==================
WARNING: ThreadSanitizer: data race (pid=5575)
  Write of size 4 at 0xffff9bf9bd28 by thread T9:
    #0 jl_new_module__ /home/user/c/julia/src/module.c:487:22 (libjulia-internal.so.1.13+0x897d4)
    #1 jl_new_module_ /home/user/c/julia/src/module.c:527:22 (libjulia-internal.so.1.13+0x897d4)
    mmtk#2 jl_f_new_module /home/user/c/julia/src/module.c:649:22 (libjulia-internal.so.1.13+0x8a968)
    mmtk#3 <null> <null> (0xffff76a21164)
    mmtk#4 <null> <null> (0xffff76a1f074)
    mmtk#5 <null> <null> (0xffff76a1f0c4)
    mmtk#6 _jl_invoke /home/user/c/julia/src/gf.c (libjulia-internal.so.1.13+0x5ea04)
    mmtk#7 ijl_apply_generic /home/user/c/julia/src/gf.c:3892:12 (libjulia-internal.so.1.13+0x5ea04)
    mmtk#8 jl_apply /home/user/c/julia/src/julia.h:2343:12 (libjulia-internal.so.1.13+0x9e4c4)
    mmtk#9 start_task /home/user/c/julia/src/task.c:1249:19 (libjulia-internal.so.1.13+0x9e4c4)

  Previous write of size 4 at 0xffff9bf9bd28 by thread T10:
    #0 jl_new_module__ /home/user/c/julia/src/module.c:487:22 (libjulia-internal.so.1.13+0x897d4)
    #1 jl_new_module_ /home/user/c/julia/src/module.c:527:22 (libjulia-internal.so.1.13+0x897d4)
    mmtk#2 jl_f_new_module /home/user/c/julia/src/module.c:649:22 (libjulia-internal.so.1.13+0x8a968)
    mmtk#3 <null> <null> (0xffff76a21164)
    mmtk#4 <null> <null> (0xffff76a1f074)
    mmtk#5 <null> <null> (0xffff76a1f0c4)
    mmtk#6 _jl_invoke /home/user/c/julia/src/gf.c (libjulia-internal.so.1.13+0x5ea04)
    mmtk#7 ijl_apply_generic /home/user/c/julia/src/gf.c:3892:12 (libjulia-internal.so.1.13+0x5ea04)
    mmtk#8 jl_apply /home/user/c/julia/src/julia.h:2343:12 (libjulia-internal.so.1.13+0x9e4c4)
    mmtk#9 start_task /home/user/c/julia/src/task.c:1249:19 (libjulia-internal.so.1.13+0x9e4c4)

  Location is global 'jl_new_module__.mcounter' of size 4 at 0xffff9bf9bd28 (libjulia-internal.so.1.13+0x3dbd28)
```

Author: xal-0

src/module.c

@@ -482,9 +482,10 @@ static jl_module_t *jl_new_module__(jl_sym_t *name, jl_module_t *parent)
     m->parent = parent ? parent : m;
     m->istopmod = 0;
     m->uuid = uuid_zero;
-    static unsigned int mcounter; // simple counter backup, in case hrtime is not incrementing
+    static _Atomic(unsigned int) mcounter; // simple counter backup, in case hrtime is not incrementing
+    unsigned int count = jl_atomic_fetch_add_relaxed(&mcounter, 1);
     // TODO: this is used for ir decompression and is liable to hash collisions so use more of the bits
-    m->build_id.lo = bitmix(jl_hrtime() + (++mcounter), jl_rand());
+    m->build_id.lo = bitmix(jl_hrtime() + count, jl_rand());
     if (!m->build_id.lo)
         m->build_id.lo++; // build id 0 is invalid
     m->build_id.hi = ~(uint64_t)0;