pool_allocator_nointr is a lie

[David Gwynne]

but we can build a truth on the lie.

how about this?

there's probably some fuzz with this diff cos i pulled it out of a
bigger one.

Index: sys/pool.h
===================================================================
RCS file: /cvs/src/sys/sys/pool.h,v
retrieving revision 1.55
diff -u -p -r1.55 pool.h
--- sys/pool.h  19 Dec 2014 02:15:25 -0000      1.55
+++ sys/pool.h  23 Dec 2014 04:00:05 -0000
@@ -167,6 +167,7 @@ struct pool {
 #ifdef _KERNEL
 
 extern struct pool_allocator pool_allocator_nointr;
+extern struct pool_allocator *const pool_page_allocator;
 
 struct pool_request {
        TAILQ_ENTRY(pool_request) pr_entry;
Index: kern/subr_pool.c
===================================================================
RCS file: /cvs/src/sys/kern/subr_pool.c,v
retrieving revision 1.173
diff -u -p -r1.173 subr_pool.c
--- kern/subr_pool.c    22 Dec 2014 00:33:40 -0000      1.173
+++ kern/subr_pool.c    23 Dec 2014 04:00:05 -0000
@@ -135,6 +137,8 @@ struct pool_allocator pool_allocator_noi
        pool_page_free
 };
 
+struct pool_allocator *const pool_page_allocator = &pool_allocator_nointr;
+
 void   *pool_large_alloc(struct pool *, int, int *);
 void   pool_large_free(struct pool *, void *);