Changeset 04e2a05 for tests/Makefile

configure: Let the user enable both built-in protocols and purple

There's no real risk in enabling these, since protocols/purple/purple.c
already avoids adding duplicate protocols in purple_initmodule():

/* If we already have this one (as a native module), don't

add a libpurple duplicate. */

if( find_protocol( prot->info->id ) )

continue;