[CORE] Fixup IO access functions

The IO access functions are very important to architectures like
x86.

This patch fixes prototype of all IO access functions and adds
few legacy memory read/write operations.

Signed-off-by: Anup Patel <anup@brainfault.org>
[DRIVERS] Fix drivers to reflect changes vmm_host_io.h

Signed-off-by: Anup Patel <anup@brainfault.org>