libcacard: build fixes

libcacard: build fixes

Link trace objects to fix these errors:
  LINK  vscclient
oslib-posix.o: In function `trace_qemu_vfree':
/src/qemu/obj-amd64/./trace.h:39: undefined reference to `trace1'
oslib-posix.o: In function `trace_qemu_memalign':
/src/qemu/obj-amd64/./trace.h:31: undefined reference to `trace3'
oslib-posix.o: In function `trace_qemu_vmalloc':
/src/qemu/obj-amd64/./trace.h:35: undefined reference to `trace2'

Add LDFLAGS to vscclient link command.

Clean up also in subdirectories of libcacard.

Use quiet-command for sed invocation.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Acked-by: Alon Levy <alevy@redhat.com>