scripts/coverity: Drop --enable-libnfs from configure

The environment we do our coverity build in (amd64-fedora-container) has just upgraded to Fedora 43. This ships with libnfs version 16.2.0. We can't currently build against that: in commit e2d98f257138 we added a requirement to meson.build that libnfs be < 6.0.0, because of an upstream API change that we haven't yet updated block/nfs.c to handle. The result is that the coverity CI job currently fails in configure: Dependency libnfs found: NO. Found 16.2.0 but need: '<6.0.0' ; matched: '>=1.9.3' Run-time dependency libnfs found: NO ../meson.build:1150:11: ERROR: Dependency lookup for libnfs with method 'pkgconfig' failed: Invalid version, need 'libnfs' ['<6.0.0'] found '16.2.0'. Fix the coverity builds by dropping --enable-libnfs. This means we will no longer have coverage of block/nfs.c until/unless we do that update to handle the new libnfs API. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Message-id: 20260226111001.1021810-1-peter.maydell@linaro.org