Floss: lower log verbosity of |UIPC_Send|

There is little interest in general to see all occurences of this
function call, and it could spam report logs really bad.

This CL lowers its verbosity.

Bug: 329298322
Test: m Bluetooth
Flag: EXEMPT log verbosity change
Change-Id: I907844759dbfd3066f3499e0bed174ce38463828