efi_driver: add init function to EFI block driver

For handling added and removed block devices we need to register events
which has to be done when the driver is installed.

This patch only creates an empty init function that will be filled with
code later on. The function needs to be called before any EFI block devices
are used. Move the efi_driver_init() call to early init.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/efi_driver/efi_block_device.c b/lib/efi_driver/efi_block_device.c
index f440067..bd36888 100644
--- a/lib/efi_driver/efi_block_device.c
+++ b/lib/efi_driver/efi_block_device.c
@@ -197,6 +197,17 @@
 	return ret;
 }
 
+/**
+ * efi_bl_init() - initialize block device driver
+ *
+ * @this:	extended driver binding protocol
+ */
+static efi_status_t
+efi_bl_init(struct efi_driver_binding_extended_protocol *this)
+{
+	return EFI_SUCCESS;
+}
+
 /* Block device driver operators */
 static const struct blk_ops efi_blk_ops = {
 	.read	= efi_bl_read,
@@ -215,6 +226,7 @@
 static const struct efi_driver_ops driver_ops = {
 	.protocol	= &efi_block_io_guid,
 	.child_protocol = &efi_block_io_guid,
+	.init		= efi_bl_init,
 	.bind		= efi_bl_bind,
 };