efi_loader: Select EVENT as well

Fixes

WARNING: unmet direct dependencies detected for EVENT_DYNAMIC
  Depends on [n]: EVENT [=n]
  Selected by [y]:
  - EFI_LOADER [=y] && OF_LIBFDT [=y] && ...

and the succeeding build breakage.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index eb2d6fd..e2a1a5a 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -16,6 +16,7 @@
 	default y if !ARM || SYS_CPU = armv7 || SYS_CPU = armv8
 	select CHARSET
 	select DM_EVENT
+	select EVENT
 	select EVENT_DYNAMIC
 	select LIB_UUID
 	imply PARTITION_UUIDS