include: Make unprivilege load/store functions as non-inline functions

Currently, the unprivilege load/store functions are inline functions.

We will be extending these functions to track whether a page/access
fault occurs when we execute unprivilege load/store instruction.

To make things simpler and debugable, we reduce number of places which
can potentially generate a page/access fault by making all unprivilege
load/store functions as regular (non-inline) functions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>