nios2: use asm-generic/mmu_context.h for no-op implementations

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

sched/headers: Prepare to remove the <linux/mm_types.h> dependency from <linux/sched.h>

Update code that relied on sched.h including various MM types for them.

This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

nios2: Process management

This patch adds support for thread creation and context switching.

Signed-off-by: Ley Foon Tan <lftan@altera.com>