dell-smbios: make the SMBIOS buffer static

As dell-laptop has been changed to always retrieve a pointer to the
SMBIOS buffer using dell_smbios_get_buffer(), the SMBIOS buffer can be
marked static.
Signed-off-by: NMichał Kępień <kernel@kempniu.pl>
Reviewed-by: NPali Rohár <pali.rohar@gmail.com>
Signed-off-by: NDarren Hart <dvhart@linux.intel.com>

drivers/platform/x86/dell-smbios.c

@@ -31,8 +31,7 @@ struct calling_interface_structure {
 	struct calling_interface_token tokens[];
 } __packed;
 
-struct calling_interface_buffer *buffer;
-EXPORT_SYMBOL_GPL(buffer);
+static struct calling_interface_buffer *buffer;
 static DEFINE_MUTEX(buffer_mutex);
 
 static int da_command_address;

drivers/platform/x86/dell-smbios.h

@@ -35,7 +35,6 @@ struct calling_interface_token {
 	};
 };
 
-extern struct calling_interface_buffer *buffer;
 extern struct calling_interface_token *da_tokens;
 
 struct calling_interface_buffer *dell_smbios_get_buffer(void);