[gcc r13-3182] libgfortran: Use `__gthread_t` instead of `pthread_t`

[Jonathan Yong <jyong@gcc.gnu.org>]

https://gcc.gnu.org/g:decbb5bf7cc7317fefa53f0d64082cf020e85e42

commit r13-3182-gdecbb5bf7cc7317fefa53f0d64082cf020e85e42
Author: LIU Hao <lh_mouse@126.com>
Date:   Fri May 27 23:12:48 2022 +0800

    libgfortran: Use `__gthread_t` instead of `pthread_t`
    
    It used to cause errors if a thread model other than `posix` was selected,
    which looks like a leftover from a79878585a1c5e32bafbc6d1e73f91fd6e4293bf.
    
    libgfortran/
            * io/async.h (struct async_unit): Use `__gthread_t` instead
            of `pthread_t`.
    
    Signed-off-by: LIU Hao <lh_mouse@126.com>
    Signed-off-by: Jonathan Yong <10walls@gmail.com>

Diff:
---
 libgfortran/io/async.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libgfortran/io/async.h b/libgfortran/io/async.h
index efd542a45e8..d57722a95e4 100644
--- a/libgfortran/io/async.h
+++ b/libgfortran/io/async.h
@@ -351,7 +351,7 @@ typedef struct async_unit
   struct adv_cond work;
   struct adv_cond emptysignal;
   struct st_parameter_dt *pdt;
-  pthread_t thread;
+  __gthread_t thread;
   struct transfer_queue *head;
   struct transfer_queue *tail;