clamav: all; init; add only non-empty parameters

[systemcrash]

Gate all parameters behind -n, a not-empty check.

Closes #27430

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Description:

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• OpenWrt Version:
• OpenWrt Target/Subtarget:
• OpenWrt Device:

---

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[wehagy]

Need to bump PKG_RELEASE.

[systemcrash]

done

[wehagy]

Unrelated CI error, maybe related to #27478 (comment):

   ERROR: package/feeds/packages_ci/rust [host] failed to build.

Building bootstrap
error: failed to calculate checksum of: /builder/build_dir/target-x86_64_musl/host/rustc-1.90.0-src/vendor/serde-1.0.215/Cargo.toml.orig

Caused by:
  failed to open file `/builder/build_dir/target-x86_64_musl/host/rustc-1.90.0-src/vendor/serde-1.0.215/Cargo.toml.orig`

Caused by:
  No such file or directory (os error 2)
failed to run: /builder/build_dir/target-x86_64_musl/host/rustc-1.90.0-src/build/x86_64-unknown-linux-gnu/stage0/bin/cargo build --manifest-path /builder/build_dir/target-x86_64_musl/host/rustc-1.90.0-src/src/bootstrap/Cargo.toml -Zroot-dir=/builder/build_dir/target-x86_64_musl/host/rustc-1.90.0-src
Build completed unsuccessfully in 0:00:16
make[2]: *** [Makefile:108: /builder/build_dir/target-x86_64_musl/host/rustc-1.90.0-src/.built] Error 1
make[2]: Leaving directory '/feed/lang/rust'
time: package/feeds/packages_ci/rust/host-compile#37.37#24.46#60.37

Merging, thanks.