v4l2: Unify one instance of reading/storing errno

Signed-off-by: Martin Storsjö <martin@martin.st>
Merge commit 'b776113e5d4a56759615196de98efe802e95a6b6'

* commit 'b776113e5d4a56759615196de98efe802e95a6b6':
  v4l2: Unify one instance of reading/storing errno

Conflicts:
	libavdevice/v4l2.c

See: 60950adc18fe145a235211e75da68ab07123fcaa
Merged-by: Michael Niedermayer <michaelni@gmx.at>
libavcodec/ppc/me_cmp.c : factorize little and big endian code

add marcos GET_PERM() LOAD_PIX() for POWER LE

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
libavcodec/ppc/me_cmp.c : support little endian in sse8_altivec(), hadamard8_diff8x8_altivec() and hadamard8_diff16x8_altivec()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>