file_to_sdram is used to load an initrd. The resource size is
then used to pass the initrd size to Linux. This means that
the resource size must exactly match the initrd size. Currently
this is not the case since we request the sdram region in chunks
of 8 Kbytes. Fix this by adjusting the resource size when the file
is loaded.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>