* Add support for marker type relocations. These mark areas

	* Add support for marker type relocations.  These mark areas
	of interest to the linker.  ENTRY/EXIT relocations for SOM are
	an example of marker relocations.
	* write.c (write_relocs): Instead of assuming size of a relocation
	is 4 bytes, pick up the size from relocation itself.
	(fixup_segment): Do not complain that a value is too small for
	marker relocations.