nimble/ll: Fix handling LL_PHY_UPDATE_IND as a master
nimble/ll: Fix handling LL_PHY_UPDATE_IND as a master

We should response with LL_UNKNOWN_RSP

This should fix LL/PAC/MAS/BV-01

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