Meson: Fix libxml2 fallback, find_library() adds 'lib' prefix

1 job from meson-fallback in 4 minutes and 19 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
failed #162390
non_aws
build

00:04:19

 
Name Stage Failure
failed
build Test
make[2]: Leaving directory '/builds/xclaesse/libsoup/build/tests'
make[1]: *** [Makefile:1914: check] Error 2
make[1]: Leaving directory '/builds/xclaesse/libsoup/build/tests'
make: *** [Makefile:566: check-recursive] Error 1
Uploading artifacts...
/builds/xclaesse/libsoup/build/config.log: found 1 matching files
/builds/xclaesse/libsoup/build/tests/test-suite.log: found 1 matching files
Uploading artifacts to coordinator... ok id=162390 responseStatus=201 Created token=QpTWG46L
ERROR: Job failed: exit code 1