MN10300: Fix the vmlinux ldscript

Fix the MN10300 vmlinux ldscript.  It needs to use various macros from
asm-generic/vmlinux.lds.h to correctly include all that it needs to.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>