Fix a couple of RTEMS target configure problems

[Nick Clifton]

Hi Joel

> 	* bfd/config.bfd (i[3456]86-rtems*, m68k-*-rtems*):
> 	Correct so default is ELF not coff as on 2.10 release branch.
> 	* gas/configure.in (i[3456]86-rtems*, m68k-*-rtems*):
> 	Correct so default is ELF not coff as on 2.10 release branch.
> 	* gas/configure.in (sh-*-rtems*): Set bfd_gas to "yes".
> 	* ld/configure.tgt (i[3456]86-rtems*, m68k-*-rtems*):
> 	Correct so default is ELF not coff as on 2.10 release branch.

Approved.

Cheers
        Nick