Switch qmmp to USES=libarchive

The LIB_DEPENDS line can also be satisfied by base libarchive, which
then leads to problems at configure time because the CMake code looks for
ports libarchive. This is hidden as long as CMake depends on the ports
version of libarchive.

PR: 226538
Approved by: tcberner (mentor), liangtai.s16@gmail.com (maintainer)
Differential Revision: https://reviews.freebsd.org/D14655