nimble/phy: Change PPI channels for debug pins
nimble/phy: Change PPI channels for debug pins

Let's use last 3 available channels instead of something in the middle.

X-Original-Commit: 8a6d9fd72034150cad021bba84c925c21ec45f9a

apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble