Fix problems with >8 bit input
Fix problems with >8 bit input

Enforce bit depth promised by --input-bitdepth to avoid crashes when
larger values are provided.

Do endianess byte swap for all bytes when the buffer gets extended
to multiple of 8 pixels, and not just the number of input pixels.

Don't swap bytes on a little-endian system.

ultravideo/kvazaar,ultravideo/kvazaar,ultravideo/kvazaar,ultravideo/kvazaar,ultravideo/kvazaar