server: remove dep on libcacard
server: remove dep on libcacard

Only the client needs this, and erronously using SPICE_REQUIRES
results in libcacard dep in spice-server.pc, which is then dragged
into qemu when linking, beeing used instead of the builtin libcacard.

virtualAMP/spiceplay,virtualAMP/spiceplay,virtualAMP/spiceplay,virtualAMP/spiceplay