ARM: rmobile: Shrink the TPL

Shrink the TPL by using tiny printf and tiny memset by default.
This removes the biggest symbol -- vsnprintf_internal -- from
the TPL and reduces the text segment by about 2 kiB.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>