m32r: Cleanup linker script using new linker script macros.

This patch is largely a straightforward conversion.  One thing to note
is that the new macros use fewer separate output sections than the old
code; this should have no functional impact but is relevant for people
objdumping vmlinux files.

Also note that it moves the .data.init_task output sections inside
_edata.

Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>