[binutils-gdb] Add some casts for building on musl.

[sergiodj+buildbot at redhat dot com]

*** TEST RESULTS FOR COMMIT d41401ace01c234f42697e190a2ac95991780626 ***

Author: Doug Evans <dje@google.com>
Branch: master
Commit: d41401ace01c234f42697e190a2ac95991780626

Add some casts for building on musl.

gdb/ChangeLog:

	* linux-thread-db.c (find_new_threads_callback): Cast ti.ti_tid to
	unsigned long for debug_printf.
	(thread_db_pid_to_str): Ditto.

gdb/gdbserver/ChangeLog:

	* thread-db.c (find_one_thread): Cast ti.ti_tid to unsigned long
	for debug_printf.
	(attach_thread, find_new_threads_callback): Ditto.