tpm: atmel: Drop PPC64 specific MMIO setup

The PPC64 specific MMIO setup open codes DT address functions rather
than using standard address parsing functions. The open-coded version
fails to handle any address translation and is not endian safe.

I haven't found any evidence of what platform used this. The only thing
that turned up was a PPC405 platform, but that is 32-bit and PPC405
support is being removed as well. CONFIG_TCG_ATMEL is not enabled for
any powerpc config and never was. The support was added in 2005 and
hasn't been touched since.

Rather than try to modernize and fix this code, just remove it.

[jarkko: fixed couple of style issues reported by checkpatch.pl --strict
 and put offset into parentheses in the macro declarations.]
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>