libjpeg-turbo: add package

libjpeg-turbo: add package

Libjpeg-turbo is a fork of jpeg-6b, which includes MMX, SSE and NEON
acceleration and other performance enhancements. It is meant to be
ABI/API compatible with the Independent JPEG Group's (IJG) jpeg
implementation. Since its initial release, it also emulates jpeg 7 or
8, and has been adopted as the system jpeg library of Fedora, and an
option in Gentoo.

The SIMD acceleration provides a 2-4x speedup. On non-SIMD machines
the enhancements provides up to a 25% improvement.

Signed-off-by: Ian Leonard <antonlacon@gmail.com>
Signed-off-by: Florian Fainelli <florian@openwrt.org>
git-svn-id: svn://svn.openwrt.org/openwrt/packages@34580 3c298f89-4303-0410-b956-a3cf2f4a3e73