ACPI: Do not export functions that are only used in osl.c

The functions acpi_os_map_generic_address() and
acpi_os_unmap_generic_address() are only used in drivers/acpi/osl.c,
so make them static and remove the extern definitions of them from
include/linux/acpi_io.h.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index c90c76a..ff2189d 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -397,7 +397,7 @@
 		__acpi_unmap_table(virt, size);
 }
 
-int acpi_os_map_generic_address(struct acpi_generic_address *addr)
+static int acpi_os_map_generic_address(struct acpi_generic_address *addr)
 {
 	void __iomem *virt;
 
@@ -413,9 +413,8 @@
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(acpi_os_map_generic_address);
 
-void acpi_os_unmap_generic_address(struct acpi_generic_address *addr)
+static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr)
 {
 	void __iomem *virt;
 	unsigned long flags;
@@ -433,7 +432,6 @@
 
 	acpi_os_unmap_memory(virt, size);
 }
-EXPORT_SYMBOL_GPL(acpi_os_unmap_generic_address);
 
 #ifdef ACPI_FUTURE_USAGE
 acpi_status