* gdb_string.h: Moved to ...

	* gdb_string.h: Moved to ...
	* common/gdb_string.h: ... here.
	* common/vec.h: Remove #ifndef GDBSERVER conditional inclusion of
	gdb_string.h and gdb_assert.h.

	gdbserver/
	* configure.ac: Add check for strstr.
	* config.in: Regenerate.
	* configure: Regenerate.

	* linux-thread-db.c: #include "gdb_vecs.h".
	(try_thread_db_load_from_pdir_1): New arg "subdir".  All callers
	updated.
	(try_thread_db_load_from_pdir): New arg "subdir".  All callers updated.
	(thread_db_load_search): Use a vector to iterate over path elements.
	Handle text appearing after "$pdir".

	gdbserver/
	* Makefile.in (SFILES): Add gdb_vecs.c.
	(OBS): Add gdb_vecs.o.
	(gdb_vecs_h, host_defs_h): New variables.
	(thread-db.o): Add $(gdb_vecs_h) dependency.
	(gdb_vecs.o): New rule.
	* thread-db.c: #include "gdb_vecs.h".
	(thread_db_load_search): Use a vector to iterate over path elements.
	Handle text appearing after "$pdir".