Floss: Add dumpsys command

This patch allows developers to get diagnostics information
from Fluoride's dump interface.
It helps on debugging LE audio connection information and parameters
negotiated with remote devices.

Bug: 327542410
Tag: #floss
Test: btclient -c dumpsys
Test: m com.android.btservices
Floag: EXEMPT, floss only change
Change-Id: I1957ea81b0b4bdab0297b5182c0920dbd53ee059