sh: consolidate CONFIG_SYS_CPU defines

Now each board selects one of CONFIG_CPU_SH2, CONFIG_CPU_SH3,
CONFIG_CPU_SH4, so let's move CONFIG_SYS_CPU definition to
arch/sh/Kconfig.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
22 files changed