sh: Fix the sparsemem disabled build.

The introduction of MAX_PHYSMEM_BITS in to the initial cpuinfo struct
causes a build error when sparsemem is disabled and asm/sparsemem.h is
not brought in by other means. Include it explicitly.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/kernel/setup.c

@@ -41,6 +41,7 @@
 #include <asm/smp.h>
 #include <asm/mmu_context.h>
 #include <asm/mmzone.h>
+#include <asm/sparsemem.h>
 
 /*
  * Initialize loops_per_jiffy as 10000000 (1000MIPS).