staging: fix the build breakage cuased by telephony drivers

Fix build error caused by commit:

6222d7a1
telephony: Move to staging

The telephony driver was moved to staging but the Makefiles
weren't updated

Cc: Joe Perches <joe@perches.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>