ACPI: make ec_transaction not extern

Fix sparse warning:
drivers/acpi/ec.c:372:12: warning: function 'ec_transaction' with external linkage has definition
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/ec.c

@@ -369,7 +369,7 @@ int ec_write(u8 addr, u8 val)
 
 EXPORT_SYMBOL(ec_write);
 
-extern int ec_transaction(u8 command,
+int ec_transaction(u8 command,
                           const u8 *wdata, unsigned wdata_len,
                           u8 *rdata, unsigned rdata_len)
 {