arm: dts: k3-am64-main: Update the location of ATF in SRAM and increase its max size

arm: dts: k3-am64-main: Update the location of ATF in SRAM and increase its max size

Due to a limitation for USB DFU boot mode, SPL load address has to be less
than  or equal to 0x70001000. So, load address of SPL and ATF have been
moved to 0x70000000 and 0x701a0000 respectively.

Also, the maximum size of ATF has been increased to 0x1c000 [1].

Therefore, update ATF's location and maximum size accordingly in the device
tree file.

[1] - https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=2fb5312f61a7de8b7a70e1639199c4f14a10b6f9

Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210604163043.12811-10-a-govindraju@ti.com