fix(PeriphDrivers): Fix dma_revb & nvic-table.c warnings

[Brandon-Hurst]

RevB DMA driver had incorrect pointer syntax. NVIC driver had an extern inside a function. These generates errors in CI workflows on third-party repositories which use later version of ARM GCC, even though the files aren't necessarily used by a build. In particular, this is blocking a PR merge due to failing CI on Adafruit's CircuitPython. Since the fixes are simple, it makes sense to just get rid of the warnings here.

adafruit/circuitpython#9667

Description

• Corrected pointer syntax in dma_revb.c. A couple functions pass srcdst as a pointer instead of a struct. In these cases a '->' instead of a '.' must be used to access members.
• Moved __isr_vector extern outside of NVIC_SetRAM in nvic_table.c. Later versions of GCC create warnings when externs are placed inside of a function.
• Added "void" argument to a function prototype in dma_revb.h

[sihyung-maxim]

I don't know why the DMA RevB drivers are included in the SDK when they're not used anywhere... and especially since no development has been done on them since around ~2020, I'm not surprised there were warnings in them. They don't follow the convention for hardware revision files either.

I think it's safe to delete these drivers entirely.

[Brandon-Hurst]

Only additional concern not covered by deleting the dma_revb drivers would be the NVIC_Table nested extern. The simple fix for this is to just move the extern to the top of the file. It can be made static as well if needed.

[Brandon-Hurst]

Removed DMA RevB drivers in latest commit