Add support for media-libs/alsa-lib (Advanced Linux Sound Architecture)

Packages describing “alsa” as local USE flag

Package “alsa” Flag Description
x11-misc/xmobar Use alsa-mixer to get the volume from soundcards.
app-emulation/qemu Enable alsa output for sound emulation
www-client/firefox-bin When pulseaudio isn't set, this prefers apulse
media-tv/mythtv Allows MythTV to directly output sound to ALSA devices
media-sound/denemo Enable alsa support through media-libs/alsa-lib
media-sound/xwax Adds support for ALSA audio input/output.
media-libs/libcanberra Enables ALSA sound driver.

All packages providing a “alsa” USE flag (133)