bash-5.2.9 lib/readline/input.c fix for Tru64

[Henry Bent]

Hi,

In bash-5.2.9 if HAVE_SELECT is set but HAVE_PSELECT is not, we still need
the "fd_set readfds;" at line 808 in lib/readline/input.c.  Found on Tru64
5.1.

Also this platform doesn't have strtoimax but config.h is still setting

#define HAVE_DECL_STRTOIMAX 1
#define HAVE_DECL_STRTOLL 1
#define HAVE_DECL_STRTOULL 1
#define HAVE_DECL_STRTOUMAX 1

even though later on it correctly realizes that HAVE_STRTOLL,
HAVE_STRTOULL, HAVE_STRTOIMAX, and HAVE_STRTOUMAX should not be set.  This
is because the Tru64 linker will still produce an executable and return
true even if the executable contains unresolved symbols.  I'm not
immediately sure of a fix for that one.

-Henry