eeepc: depends on RFKILL

EEEPC_LAPTOP uses RFKILL, so the former should depend on RFKILL.
Build errors happen when EEEPC_LAPTOP=y and RFKILL=m.

eeepc-laptop.c:(.text+0xd5a7b): undefined reference to `rfkill_allocate'
eeepc-laptop.c:(.text+0xd5b04): undefined reference to `rfkill_register'
eeepc-laptop.c:(.text+0xd5b48): undefined reference to `rfkill_allocate'
eeepc-laptop.c:(.text+0xd5bd4): undefined reference to `rfkill_register'
eeepc-laptop.c:(.text+0xd5ece): undefined reference to `rfkill_unregister'
eeepc-laptop.c:(.text+0xd5ef6): undefined reference to `rfkill_unregister'
make[1]: *** [.tmp_vmlinux1] Error 1

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Corentin Chary <corentincj@iksaif.net>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Karol Kozimor <sziwan@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>