x86: Introduce IO port control caps

Changes the way IO ports work such that instead of 'minting' IO port caps down into new
IO port caps with smaller ranges new IO port ranges must be allocated centrally from
an IO port control cap. This mechanism acts in a very similar fashion as IRQ handler/control
capabilities and ensures that allocated IO ports do not overlap. Disallowing overlapping
IO ports is necessary to ensure the CDT remains valid as capabilities are deleted.

Manual: Delete a sentence that's not valid anymore

manual: Correct manual label for X86_Page_MapIO

manual: Correct ia32 to x86 in some sections

SELFOUR-652: Remove incorrect statements about physical addresses

SELFOUR-429: Document x86 interrupt invocations

Add documentation for seL4_IRQControl_GetIOAPIC and seL4_IRQControl_GetMSI,
which only exist on x86 platforms.

SELFOUR-279: rename Wait -> Recv, add wrappers for seL4_Poll and seL4_Wait for notification objects.

This commit deprecates seL4_ReplyWait, removes seL4_NBwait completely,
and changes the return type of seL4_Wait to void (seL4_Wait should be
used for notification objects, and seL4_Recv should be used where
seL4_Wait was used previously for endpoints).

manual: notification/signalling terminology

Terminology clarification:
- synchronous endpoints -> endpoints
- asynchronous endpoints -> notifications (and notification objects)
- notify -> signal

Also minor language edits.

Revert "s/AEP/Notification/ completed commit :-("

Committed to wrong branch

This reverts commit 50810ac44a4f90f07cfe1aba6f8bf14c30f1d85d.

s/AEP/Notification/ completed commit :-(

Had forgotten the "-a", bear with me, I'm a git newbie...

Release snapshot