Commit 21d5d592a4 (package/fft_eval: new package) got last-minute
changes when comitted, changes which no longer made use of the
FFT_EVAL_TARGETS variable, but forgot to drop assignments to that
variable.
Drop them now.
Reported-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>