ims_usrloc_scscf: assignment of length missing for query_buffer in db_link_contact_to_impu()

[christoph-v]

When writing to query_buffer with the help of the snprintf() function,
the result of the functio is written to variable query_buffer_len
instead of to the query_buffer.len itself. This leads to core dump
in some cases. Replaced "_" by "." in "query_buffer_len ="

Pre-Submission Checklist

• Commit message has the format required by CONTRIBUTING guide
• Commits are split per component (core, individual modules, libs, utils, ...)
• Each component has a single commit (if not, squash them into one commit)
• No commits to README files for modules (changes must be done to docbook files
  in doc/ subfolder, the README file is autogenerated)

Type Of Change

• Small bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds new functionality)
• Breaking change (fix or feature that would change existing functionality)

Checklist:

• PR should be backported to stable branches
• Tested changes locally
• Related to issue #XXXX (replace XXXX with an open issue number)

Description

When linking a Contact to an IMPU during SIP REGISTER in S-CSCF, a core dump can happen due to missing assignment of length to query_buffer.
Added the assignment.