[POWERPC] Fix idr locking in init_new_context

We always need to serialize accesses to mmu_context_idr.

I hit this bug when testing with a small number of mmu contexts.

Signed-off-by: Sonny Rao <sonny@burdell.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
1 file changed