sparc: add export.h to arch/sparc files as required

These files are only exporting symbols, so they don't need
the full module.h header file.  Previously they were getting
access to EXPORT_SYMBOL implicitly via overuse of module.h
from within other .h files, but that is being cleaned up.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

arch/sparc/mm/generic_32.c

@@ -9,6 +9,7 @@
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/pagemap.h>
+#include <linux/export.h>
 
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>

arch/sparc/mm/generic_64.c

@@ -8,6 +8,7 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
+#include <linux/export.h>
 #include <linux/pagemap.h>
 
 #include <asm/pgalloc.h>

arch/sparc/mm/highmem.c

@@ -24,6 +24,7 @@
  */
 #include <linux/mm.h>
 #include <linux/highmem.h>
+#include <linux/export.h>
 #include <asm/pgalloc.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>