res_geolocation: Add built-in profiles

The trigger to perform outgoing geolocation processing is the
presence of a geoloc_outgoing_call_profile on an endpoint. This
is intentional so as to not leak location information to
destinations that shouldn't receive it.   In a totally dynamic
configuration scenario however, there may not be any profiles
defined in geolocation.conf.  This makes it impossible to do
outgoing processing without defining a "dummy" profile in the
config file.

This commit adds 4 built-in profiles:
  "<prefer_config>"
  "<discard_config>"
  "<prefer_incoming>"
  "<discard_incoming>"
The profiles are empty except for having their precedence
set and can be set on an endpoint to allow processing without
entries in geolocation.conf.  "<discard_config>" is actually the
best one to use in this situation.

ASTERISK-30182

Change-Id: I1819ccfa404ce59802a3a07ad1cabed60fb9480a