BUG/MAJOR: resolvers: segfault using server template without SRV RECORDs

This patch fix the issue adding a test in srvrq before registering
the server on it during server template init.

This was a regression due to commit :
3406766d57fc11478d54a6fa2d048cbfe4524a4e

This should be backported with this previous commit (until 2.0)
1 file changed