bfd/

bfd/
	* cpu-m68k.c (bfd_m68k_compatible): Treat ISA A+ and ISA B code as
	incompatible.  Likewise MAC and EMAC code.
	* elf32-m68k.c (elf32_m68k_merge_private_bfd_data): Use
	bfd_get_compatible to set the new bfd architecture.  Rely on it
	to detect incompatibilities.

gas/
	* config/tc-m68k.c (m68k_cpus): Change cpu_cf5208 entries to use
	mcfemac instead of mcfmac.

ld/testsuite/
	* ld-m68k/merge-error-1a.s, ld-m68k/merge-error-1b.s,
	* ld-m68k/merge-error-1a.d, ld-m68k/merge-error-1b.d,
	* ld-m68k/merge-error-1c.d, ld-m68k/merge-error-1d.d,
	* ld-m68k/merge-error-1e.d, ld-m68k/merge-ok-1a.d,
	* ld-m68k/merge-ok-1b.d: New tests.
	* ld-m68k/m68k.exp: Run them.