arch/tile: add a few #includes and an EXPORT to catch up with kernel changes.

The empty_zero_page[] export is required for ZERO_PAGE() module references.
The #includes are due to changes in implicit inclusion, and should of
course have been in the sources from the beginning.

Signed-off-by: Chris Metcalf <[e-mail]>

arch/tile/kernel/pci-dma.c

···
 #include <linux/mm.h>
 #include <linux/dma-mapping.h>
 #include <linux/vmalloc.h>
+#include <linux/export.h>
 #include <asm/tlbflush.h>
 #include <asm/homecache.h>
 

arch/tile/kernel/pci.c

···
 #include <linux/irq.h>
 #include <linux/io.h>
 #include <linux/uaccess.h>
+#include <linux/export.h>
 
 #include <asm/processor.h>
 #include <asm/sections.h>

arch/tile/kernel/sysfs.c

···
 #include <linux/cpu.h>
 #include <linux/slab.h>
 #include <linux/smp.h>
+#include <linux/stat.h>
 #include <hv/hypervisor.h>
 
 /* Return a string queried from the hypervisor, truncated to page size. */

arch/tile/lib/exports.c

···
 EXPORT_SYMBOL(current_text_addr);
 EXPORT_SYMBOL(dump_stack);
 
+/* arch/tile/kernel/head.S */
+EXPORT_SYMBOL(empty_zero_page);
+
 /* arch/tile/lib/, various memcpy files */
 EXPORT_SYMBOL(memcpy);
 EXPORT_SYMBOL(__copy_to_user_inatomic);