nimble/ll: Fix LL_LENGTH_REQ/RSP handling
nimble/ll: Fix LL_LENGTH_REQ/RSP handling

We should reply LL_UNKNOWN_RSP if CtrlData received from peer are
invalid [1]. This means, we only have to check if TX/RX values for time
and octets are not less than 328 and 27 respectively [2]. Any other
value received shall be accepted - we will calculate effective values
for both octets and time to be within limits anyway.

In addidion, even if LL_LENGTH_RSP does not have valid data we should
end procedure since there is no exception for this in spec [3]. We do
not apply invalid parameters, but also won't hit procedure timeout.

Core specification v5.0, Vol 6, Part B
[1] section 2.4.2
[2] section 2.4.2.21
[3] section 5.1.10

X-Original-Commit: faf673657f07b4215befe2a11ed1546a27ce4d96

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