btsnoop: Remove the ext snoop dependency on snoop socket

Snoop socket cannot be enabled by default to be CTS compliant.
External snoop dump uses same thread, external dump related
functionality is moved out of TCP socket enabling
condition check

CRs-Fixed: 951828
Change-Id: Icf51b27531a42ce257704d2c00b6e6b394cad3af
1 file changed