On some PAE architectures, the entire range of physical memory could reside
outside the 32-bit limit.  These systems need the ability to specify the
initrd location using 64-bit numbers.

This patch globally modifies the early_init_dt_setup_initrd_arch() function to
use 64-bit numbers instead of the current unsigned long.

There has been quite a bit of debate about whether to use u64 or phys_addr_t.
It was concluded to stick to u64 to be consistent with rest of the device
tree code. As summarized by Geert, "The address to load the initrd is decided
by the bootloader/user and set at that point later in time. The dtb should not
be tied to the kernel you are booting"

More details on the discussion can be found here:
https://lkml.org/lkml/2013/6/20/690
https://lkml.org/lkml/2012/9/13/544Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: NGrant Likely <grant.likely@linaro.org>