eamad: use the bytestream2 API instead of AV_RL

This is safer and possibly fixes invalid reads on truncated data.
(cherry-picked from commit 541427ab4d5b4b6f5a90a687a06decdb78e7bc3c)

CC:libav-stable@libav.org

Conflicts:
	libavcodec/eamad.c

(cherry picked from commit f9204ec56a4cf73843d1e5b8563d3584c2c05b47)
Signed-off-by: Diego Biurrun <diego@biurrun.de>
vf_select: Drop a debug av_log with an unchecked double to enum conversion

CC: libav-stable@libav.org
(cherry picked from commit a8d803a320fb08b3ad5db4fffc79abd401206905)
Signed-off-by: Diego Biurrun <diego@biurrun.de>
video4linux2: Avoid a floating point exception

This avoids a segfault in avconv_opt.c:opt_target when trying to
determine the norm.

(cherry picked from commit dc71f1958846bb1d96de43a4603983dc8450cfcc)
Signed-off-by: Diego Biurrun <diego@biurrun.de>