ARM: UniPhier: fix property names of aliases nodes of device trees

The property name of the "aliases" node should be "serial*"
to assign a desired number for the device sequence number.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
ARM: UniPhier: remove unnecessary ifdef conditional

init_page_table is only set on SPL.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
ARM: UniPhier: use DRAM area for init stack of normal image

The normal image is working on DRAM.  It is better to use DRAM also
for init stack than L2 cache.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
ARM: UniPhier: select CONFIG_SPL

Now UniPhier platform is only supported with SPL.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
ARM: UniPhier: enable CONFIG_CMD_DM

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>