qemu: disable smartcard support

* sometimes it's autodetected and fails to build:
  | /usr/bin/ld: libcacard/.libs/cac.o: Relocations in generic ELF (EM:40)
  | libcacard/.libs/cac.o: could not read symbols: File in wrong format
  | collect2: ld returned 1 exit status
  | make[1]: *** [libcacard.la] Error 1

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
libpfm4: exclude from world

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>