My original binutils patches for MIPS prelink support were against 2.17,
and reserved room for a program header without actually creating one.
The mainline (now 2.18) binutils patches ended up adding a PT_NULL
header instead.  This was needed because of mainline's SIZEOF_HEADER
relaxation and was probably a better idea anyway.

The patch below therefore teaches the prelinker to remove a PT_NULL
header if it needs to find room for a PT_LOAD header.  Tested on the
MIPS port, where it allows a sysroot built with the mainline binutils
to be fully prelinked.  Also tested on x86.

The patch involves a lot of reidentation, so for reference, I've
attached two versions: first the real patch, then the -b form.

Richard

200x-xx-xx  Richard Sandiford  <richard@codesourcery.com>

	* src/space.c (find_readonly_space): If a new PT_LOAD header is needed,
	first try removing a PT_NULL header.