add support for loongarch64

[wuruilong01]

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[tautschnig]

Patch is now included in cbmc 5.95.1-5 as just uploaded to Debian's build queue. I'll check https://buildd.debian.org/status/package.php?p=cbmc&suite=sid the next hours to confirm that this builds fine for loong64.

[tautschnig]

Builds and tests appear to have succeeded: https://buildd.debian.org/status/fetch.php?pkg=cbmc&arch=loong64&ver=5.95.1-5&stamp=1714405344&raw=0

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 16 lines in your changes are missing coverage. Please review.

Project coverage is 77.96%. Comparing base (e6e665f) to head (15b61bb).
Report is 4 commits behind head on develop.

Files	Patch %	Lines
src/util/config.cpp	0.00%	16 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #8266      +/-   ##
===========================================
+ Coverage    77.95%   77.96%   +0.01%     
===========================================
  Files         1720     1720              
  Lines       189015   188982      -33     
  Branches     18402    18391      -11     
===========================================
- Hits        147346   147345       -1     
+ Misses       41669    41637      -32     

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