mod_ladspa Does not call activate or deactivate functions on LADSPA plugin

[jyelloz]

Describe the bug
According to the LADSPA specification, if a plugin has an activate() function in its descriptor, then the host must call that function before data flow begins. The activate() function is a place where some plugins set up their internal state. The same concept applies to the deactivate() function, which must be called after no more data will flow through the plugin, except it is probably less noticeable to the user.
Currently, mod_ladspa does not call either of those functions when interacting with a LADSPA plugin which can result in weird noises upon activation of a plugin during a call.

To Reproduce
Steps to reproduce the behavior:

1. Using the vanilla configuration, also:
   1.1. Ensure the hold music is installed (make cd-moh-install or equivalent)
   1.2. Ensure mod_ladspa is enabled in your configuration
   1.3. You have the CMT plugin set installed on your system.
2. Dial into the hold music extension (9664)
3. In the freeswitch console, find the UUID of the channel for your call (possibly using show channels) and enter:
   uuid_ladspa <the uuid> start w|cmt|lpf|80
4. You may hear a brief pop or some rough noise before the filter does its normal work.

Expected behavior
When starting a LADSPA plugin, it should be activated before audio data is passed into it.

Package version or git hash

• f71a560

Trace logs
N/A

backtrace from core file
N/A