of: Fix the section mismatch warnings.

In tag next-20140407, building with CONFIG_DEBUG_SECTION_MISMATCH
enabled, the following WARNING is occured:

WARNING: drivers/built-in.o(.text.unlikely+0x2220): Section mismatch
in reference from the function __reserved_mem_check_root() to the
function .init.text:of_get_flat_dt_prop()
The function __reserved_mem_check_root() references
the function __init of_get_flat_dt_prop().
This is often because __reserved_mem_check_root lacks a __init
annotation or the annotation of of_get_flat_dt_prop is wrong.

WARNING: vmlinux.o(.text.unlikely+0xb9d0): Section mismatch in reference
from the function __reserved_mem_check_root() to the (unknown reference)
.init.data:(unknown)
The function __reserved_mem_check_root() references
the (unknown reference) __initdata (unknown).
This is often because __reserved_mem_check_root lacks a __initdata
annotation or the annotation of (unknown) is wrong.

This is cause by :
'drivers: of: add initialization code for dynamic reserved memory'.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Rob Herring <robh@kernel.org>