arm, arm926ejs: always do cpu critical inits

always do the cpu critical inits in cpu_init_crit,
and only jump to lowlevel_init, if CONFIG_SKIP_LOWLEVEL_INIT
is not defined.

Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
Cc: Wolfgang Denk <hs@denx.de>
Cc: Sandeep Paulraj <s-paulraj@ti.com>
Cc: Tom Rini <tom.rini@gmail.com>
Cc: Christian Riesch <christian.riesch@omicron.at>