pinmap_pinout : missing documentation of behavior (sets pin to PullNone)

[maclobdell]

It is easy to miss the fact that the pinmap_pinout() function also sets the pin to PullNone. This is fine as long as the hal implementation sets the pin to PullUp or PullDown if needed after calling pinmap_pinout and not before. Should be documented in comments and api documentation if possible.

[ciarmcom]

ARM Internal Ref: IOTSFW-2515