arm: pdu001: Fix early debugging UART

The changes from commit 0dba45864b2a ("arm: Init the debug UART")
prevent the early debug UART from being initialized correctly.
To fix this we not just configure the pin multiplexer but add setting up
early clocks.

Signed-off-by: Felix Brack <fb@ltec.ch>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/eets/pdu001/Makefile b/board/eets/pdu001/Makefile
index a5990ce3..35ea397 100644
--- a/board/eets/pdu001/Makefile
+++ b/board/eets/pdu001/Makefile
@@ -6,8 +6,4 @@
 # SPDX-License-Identifier: GPL-2.0+
 #
 
-ifeq ($(CONFIG_$(SPL_)SKIP_LOWLEVEL_INIT),)
-obj-y	:= mux.o
-endif
-
-obj-y	+= board.o
+obj-y	:= board.o mux.o