xtensa: avoid duplicate of IO range definitions

Define IO addresses in a single place, to make it easier to change for
non-standard memory maps.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

diff --cc arch/xtensa/include/asm/initialize_mmu.h
Simple merge

diff --cc arch/xtensa/include/asm/io.h
Simple merge

diff --cc arch/xtensa/include/asm/vectors.h
Simple merge