[PATCH] Fix AIX CI build break.

[Aditya Vidyadhar Kamath <akamath996@gmail.com>]

From: Aditya Vidyadhar Kamath <aditya.kamath1@ibm.com>

Recently AIX internal CI is broken.

The error is as follows:
--------------------------------
aix-thread.c: In function 'void sync_threadlists(pid_t)':
aix-thread.c:857:53: error: cannot convert 'thread_info' to 'thread_info*' in initialization
  857 |     for (struct thread_info *it : all_threads_safe ())
      |                                                     ^
aix-thread.c: In lambda function:
aix-thread.c:899:61: warning: declaration of 'thread' shadows a previous local [-Wshadow=compatible-local]
  899 |     thread = iterate_over_threads ([&] (struct thread_info *thread)

----------------------------------

This patch is similar to the commit https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=675a17a8a5cde1d8be86536df2ae6366ef0ec759

all_threads_safe() returns an all_threads_safe_range which is like an iterator to iterate for loops.

AIX is adjusting its code in aix-thread.c for the same.

After applying this patch,
Sample test case output:

------------
gmake check RUNTESTFLAGS='gdb.threads/thread_events.exp  CC_FOR_TARGET="/opt/freeware/bin/gcc" CXX_FOR_TARGET="/opt/freeware/bin/g++" CXXFLAGS_FOR_TARGET="-O0 -w -g -gdwarf -maix64" CFLAGS_FOR_TARGET="-O0 -w -g -gdwarf -maix64"'
gmake check-single
gmake[1]: Entering directory '/upstream_gdb/binutils-gdb/gdb/testsuite'
rm -f *core* gdb.sum gdb.log
   === gdb tests ===

Schedule of variations:
    unix

Running target unix
Using /opt/freeware/share/dejagnu/baseboards/unix.exp as board description file for target.
Using /opt/freeware/share/dejagnu/config/unix.exp as generic interface file for target.
Using /upstream_gdb/binutils-gdb/gdb/testsuite/config/unix.exp as tool-and-target-specific interface file.
Running /upstream_gdb/binutils-gdb/gdb/testsuite/gdb.threads/thread_events.exp ...

                === gdb Summary ===

/upstream_gdb/binutils-gdb/gdb/gdb version  18.0.50.20251010-git -nw -nx -q -iex "set height 0" -iex "set width 0" -data-directory /upstream_gdb/binutils-gdb/gdb/data-directory -iex "set interactive-mode on"

                === gdb Summary ===

/upstream_gdb/binutils-gdb/gdb/gdb version  18.0.50.20251010-git -nw -nx -q -iex "set height 0" -iex "set width 0" -data-directory /upstream_gdb/binutils-gdb/gdb/data-directory -iex "set interactive-mode on"

gmake[1]: Leaving directory '/upstream_gdb/binutils-gdb/gdb/testsuite'
----------------
---
 gdb/aix-thread.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/gdb/aix-thread.c b/gdb/aix-thread.c
index 1e3015d77b0..7007f76b85a 100644
--- a/gdb/aix-thread.c
+++ b/gdb/aix-thread.c
@@ -854,14 +854,14 @@ sync_threadlists (pid_t pid)
        thread exits and gets into a PST_UNKNOWN state.  So this thread
        will not run in the above for loop.  Therefore the below for loop
        is to manually delete such threads.  */
-    for (struct thread_info *it : all_threads_safe ())
+    for (thread_info &it : all_threads_safe ())
       {
-	aix_thread_info *priv = get_aix_thread_info (it);
+	aix_thread_info *priv = get_aix_thread_info (&it);
 	if (in_queue_threads.count (priv->pdtid) == 0
-		&& in_thread_list (proc_target, it->ptid)
-		&& pid == it->ptid.pid ())
+		&& in_thread_list (proc_target, it.ptid)
+		&& pid == it.ptid.pid ())
 	  {
-	    delete_thread (it);
+	    delete_thread (&it);
 	    data->exited_threads.insert (priv->pdtid);
 	  }
       }
-- 
2.41.0