fix(PeriphDrivers): Flip strong vs weak pull-up bit values

[Jake-Carter]

Description

Apparently most UGs have this flipped. Strong should set the ps field to 0, while weak should set it to 1.

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[Jake-Carter]

Pending final confirmation... don't merge yet

[sihyung-maxim]

How was this unnoticed for so long lol

[perkinsmg]

There are lots of instances where we use the enums which will now have the opposite effect to what they did before.
Mostly that's probably good, because they were probably not working correctly before.
But in at least the case of the MXC_GPIO_PAD_PULL_UP used in pins_me18.c for the UART signals, Kevin's check-in message said he was adding a weak pull-up, and Lorne recommends a weak pull-up, so I think we should change these to weak to preserve the old behaviour.

[Jake-Carter]

There are lots of instances where we use the enums which will now have the opposite effect to what they did before. Mostly that's probably good, because they were probably not working correctly before. But in at least the case of the MXC_GPIO_PAD_PULL_UP used in pins_me18.c for the UART signals, Kevin's check-in message said he was adding a weak pull-up, and Lorne recommends a weak pull-up, so I think we should change these to weak to preserve the old behaviour.

@perkinsmg updated in 1717e1a