libhugetlbfs: fix packaging

Libhugetlbs doesn't generate proper .so.X libs, only two .so files. Package those in ${PN} and silence the resulting QA warning. This fixes:

 ERROR: QA Issue: libhugetlbfs-tests rdepends on libhugetlbfs-dev

Signed-off-by: Koen Kooi <koen.kooi@linaro.org>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>