(enc|dec)_neon: use vcreate_*() where appropriate

this is more portable than {} initialization.
more involved cases are left for a follow-up.

Change-Id: If8783423d17e90694b168a64ba313ed62ce2cc17
lossless_neon: use vcreate_*() where appropriate

this is more portable than {} initialization.
more involved cases are left for a follow-up.

Change-Id: If7e111864f287ea0a5de6311454aeda37afbb52a
Always reinit VP8TransformWHT instead of hard-coding

Change-Id: I2012749ed29bd166d2a96555372f0d9baa784385
Merge "(enc|dec)_neon: use vcreate_*() where appropriate"
Merge "lossless_neon: use vcreate_*() where appropriate"
fix missing WebPInitAlphaProcessing call for premultiplied colorspace output

(lossless only)

Change-Id: Ic2d01c8cf9bc1082f07f348733461eb2ee30288a