[wp] Please the linter

headers/header_spec.txt

src/plugins/reduc/Reduc.mli

src/plugins/reduc/collect.ml

src/plugins/reduc/collect.mli

src/plugins/reduc/hyp.ml

src/plugins/reduc/hyp.mli

src/plugins/reduc/misc.ml

src/plugins/reduc/misc.mli

src/plugins/reduc/reduc_options.ml

src/plugins/reduc/reduc_options.mli

src/plugins/reduc/register.ml

src/plugins/reduc/value2acsl.ml

src/plugins/reduc/value2acsl.mli

src/plugins/wp/MemDebug.ml

src/plugins/wp/MemDebug.mli

src/plugins/wp/MemVal.ml

src/plugins/wp/MemVal.mli