Bluetooth: Add initial implementation of CIS connections

This adds the initial implementation of CIS connections and introduces
the ISO packets/links.

== Central: Set CIG Parameters, create a CIS and Setup Data Path ==

> tools/isotest -s <address>

< HCI Command: LE Extended Create... (0x08|0x0043) plen 26
...
> HCI Event: Command Status (0x0f) plen 4
      LE Extended Create Connection (0x08|0x0043) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 31
      LE Enhanced Connection Complete (0x0a)
      ...
< HCI Command: LE Create Connected... (0x08|0x0064) plen 5
...
> HCI Event: Command Status (0x0f) plen 4
      LE Create Connected Isochronous Stream (0x08|0x0064) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 29
      LE Connected Isochronous Stream Established (0x19)
      ...
< HCI Command: LE Setup Isochronou.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257
< HCI Command: LE Setup Isochronou.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257

== Peripheral: Accept CIS and Setup Data Path ==

> tools/isotest -d

 HCI Event: LE Meta Event (0x3e) plen 7
      LE Connected Isochronous Stream Request (0x1a)
...
< HCI Command: LE Accept Co.. (0x08|0x0066) plen 2
...
> HCI Event: LE Meta Event (0x3e) plen 29
      LE Connected Isochronous Stream Established (0x19)
...
< HCI Command: LE Setup Is.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257
< HCI Command: LE Setup Is.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>