* configure.in: Call BFD_NEEDED_DECLARATION on strstr and
realloc.
* acconfig.h (NEED_DECLARATION_STRSTR): New macro.
(NEED_DECLARATION_REALLOC): New macro.
* configure, config.in: Rebuild.
* sysdep.h (strstr): Declare if NEED_DECLARATION_STRSTR.
(realloc): Declare if NEED_DECLARATION_REALLOC.
(AC_CHECK_HEADERS): Check for sys/time.h
(AC_HEADER_TIME): Add macro.
* configure: Rebuild.
* sysdep.h: Use TIME_WITH_SYS_TIME and HAVE_SYS_TIME_H
to control what combination of <time> and <sys/time.h>
get included.