Move TEMP_STACK to STACK_BASE for barebox

As the DDR is available from barebox boot, there is no need to use IRAM memory
for a temporary stack (and this interferes with Trustzone protection). Instead,
just use the same location as STACK_BASE - the same value that will be used just
two or three functions later anyway!

Change-Id: I17fb78d2294667a0e6c18a51bd7918f8a7007335
1 file changed