m68k: merge m68k and m68knommu arch directories

There is a lot of common code that could be shared between the m68k
and m68knommu arch branches. It makes sense to merge the two branches
into a single directory structure so that we can more easily share
that common code.

This is a brute force merge, based on a script from Stephen King
<sfking@fdwdc.com>, which was originally written by Arnd Bergmann
<arnd@arndb.de>.

> The script was inspired by the script Sam Ravnborg used to merge the
> includes from m68knommu. For those files common to both arches but
> differing in content, the m68k version of the file is renamed to
> <file>_mm.<ext> and the m68knommu version of the file is moved into the
> corresponding m68k directory and renamed <file>_no.<ext> and a small
> wrapper file <file>.<ext> is used to select between the two version. Files
> that are common to both but don't differ are removed from the m68knommu
> tree and files and directories that are unique to the m68knommu tree are
> moved to the m68k tree. Finally, the arch/m68knommu tree is removed.
>
> To select between the the versions of the files, the wrapper uses
>
> #ifdef CONFIG_MMU
> #include <file>_mm.<ext>
> #else
> #include <file>_no.<ext>
> #endif

On top of this file merge I have done a simplistic merge of m68k and
m68knommu Kconfig, which primarily attempts to keep existing options and
menus in place. Other than a handful of options being moved it produces
identical .config outputs on m68k and m68knommu targets I tested it on.

With this in place there is now quite a bit of scope for merge cleanups
in future patches.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

arch/m68k/kernel/init_task.c

@@ -0,0 +1,36 @@
+/*
+ *  linux/arch/m68knommu/kernel/init_task.c
+ */
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/init_task.h>
+#include <linux/fs.h>
+#include <linux/mqueue.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+
+static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
+static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
+/*
+ * Initial task structure.
+ *
+ * All other task structs will be allocated on slabs in fork.c
+ */
+__asm__(".align 4");
+struct task_struct init_task = INIT_TASK(init_task);
+
+EXPORT_SYMBOL(init_task);
+
+/*
+ * Initial thread structure.
+ *
+ * We need to make sure that this is 8192-byte aligned due to the
+ * way process stacks are handled. This is done by having a special
+ * "init_task" linker map entry..
+ */
+union thread_union init_thread_union __init_task_data =
+	{ INIT_THREAD_INFO(init_task) };
+