ARM: S3C64XX: fix __initdata section mismatch

smdk6410_b_pwr_5v_data is marked as __initdata, but referenced
from a structure that is not:

WARNING: arch/arm/mach-s3c64xx/built-in.o(.data+0x4c5c): Section mismatch in reference from the variable smdk6410_b_pwr_5v_data to the (unknown reference) .init.data:(unknown)

This removes the annotation to avoid an invalid pointer access
when the regulator driver accesses this variable.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kukjin Kim <kgene@kernel.org>