Due to commit:

    5de813b6  ARM: Eliminate decompressor -Dstatic= PIC hack

The data section will be discarded for the decompressor, thus move the
static variables into BSS section by initializing them at run time.
Reported-by: NJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: NEric Miao <eric.y.miao@gmail.com>