[BUG] Documented default value for default_q is not 0. A useful value also isn't available in the event_route

[NormB]

OpenSIPS version you are running

Running master branch

Describe the bug

The documentation for the default_q value is located here: https://opensips.org/html/docs/modules/devel/registrar.html#param_default_q

Specifically "Default value is 0.".

However, the module sets the default value to Q_UNSPECIFIED.

The file qvalue.h has this comment:

Value Q_UNSPECIFIED (which is in fact -1) has a special meaning, 
it means that the q value is not known and the parameter should not
be printed when printing Contacts, implementations will then use
implementation specific pre-defined values.

The problem is that the qval printed in a fired event is not able to be printed properly as shown when printing $param(qval)

NOTICE:[E_UL_CONTACT_UPDATE] qval[18446744073709551615]

To Reproduce

Expected behavior

Relevant System Logs

OS/environment information

• Operating System:
• OpenSIPS installation:
• other relevant information:

Additional context

[NormB]

Working perfectly, thank you.

Apr 26 10:26:13 [70] NOTICE:[E_UL_CONTACT_INSERT]  QVal[-1]