PWM: Add the ability to invert the output directly in PWM

Create Signal Bundles vs just Pins

remove duplicate ResetCatchAndSync definition

spi: put a request buffer infront of SPI

This will prevent SPI from blocking other pbus requests.

Updates to go with the fpga-shells directory

mockaon: Adds logic to detect external rtc toggles

spi: Fix invalid D channel response when flash interface is disabled

Issue: When the memory-mapped flash region is accessed while the flash
read mode is disabled (fctrl.en flag is clear), the SPI flash controller
generates an invalid response on the D channel.
This may cause the TileLink bus to deadlock.

Workaround: Software should avoid accessing the memory-mapped flash
region when the SPI controller is not in the flash read mode.

Seperate GPIO Peripheral Functionality

* periphery: peripherals now in coreplex

* use fromAsyncFIFOMaster