SFI: fix compiler warnings

drivers/sfi/sfi_core.c:164:26: warning: no previous prototype for ‘sfi_map_table’ [-Wmissing-prototypes]
drivers/sfi/sfi_core.c:192:6: warning: no previous prototype for ‘sfi_unmap_table’ [-Wmissing-prototypes]

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/sfi/sfi_core.c

@@ -161,7 +161,7 @@ static int sfi_verify_table(struct sfi_table_header *table)
  * Check for common case that we can re-use mapping to SYST,
  * which requires syst_pa, syst_va to be initialized.
  */
-struct sfi_table_header *sfi_map_table(u64 pa)
+static struct sfi_table_header *sfi_map_table(u64 pa)
 {
 	struct sfi_table_header *th;
 	u32 length;
@@ -189,7 +189,7 @@ struct sfi_table_header *sfi_map_table(u64 pa)
  * Undoes effect of sfi_map_table() by unmapping table
  * if it did not completely fit on same page as SYST.
  */
-void sfi_unmap_table(struct sfi_table_header *th)
+static void sfi_unmap_table(struct sfi_table_header *th)
 {
 	if (!TABLE_ON_PAGE(syst_va, th, th->len))
 		sfi_unmap_memory(th, TABLE_ON_PAGE(th, th, th->len) ?