libwebp-1.2.4

- 8/4/2022: version 1.2.4
  This is a binary compatible release.
  * restore CMake libwebpmux target name for compatibility with 1.2.2 (#575)
  * fix lossless crunch mode encoding with WEBP_REDUCE_SIZE
    (chromium: #1345547, #1345595, #1345772, #1345804)

1. 7c76255 autoconf: update ax_pthread.m4 by James Zern · 12 years ago
2. 1d40a8b configure: add pthread detection by James Zern · 13 years ago
3. b247a3b Create the m4 directory, and also place .gitignore in there for libtool. by Pascal Massimino · 15 years ago