MFH: r445836 r445837 r445838 r445839 r445840

multimedia/{lib,}x264: update to 0.148.2795

• yasm is only used by libx264, so move ASM option there
• yasm is only used on x86, other archs use GNU as
• enable FFMS, LAVF, SWSCALE by default to make package more useful

Changes: https://git.videolan.org/?p=x264.git;a=shortlog;h=aaa9aa83a111ed6f1db253d5afa91c5fc844583f
ABI: https://abi-laboratory.pro/tracker/timeline/x264/
PR: 220694
Approved by: koobs (maintainer)
Differential Revision: https://reviews.freebsd.org/D11566
Approved by: ports-secteam (junovitch)