hdf5_msb

Extract a subroutine, H5F_vfd_swmr_process_eot_queue(), from the
end-of-tick processing macro.  H5F_vfd_swmr_process_eot_queue() looks
for files due for end-of-tick processing and calls either the reader or
writer EOT routine.

Always call the reader/writer EOT routines with an actual H5F_t instead
of NULL.