avcodec/Makefile: Only compile nvenc.o if needed

This fixes compilation errors in case nvenc is enabled
(e.g. autodected) with both nvenc-based encoders disabled
because nvenc uses ff_alloc_a53_sei(), yet only the nvenc-based
encoders require atsc_a53.
(This error does not manifest itself in case of static linking
(nothing pulls in nvenc.o), but it exists with shared builds.)

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>

0 files changed, 0 insertions, 0 deletions