reduce `exec`s by four, and eliminate logic bug

alsa-project/alsa-utils pull request #205 was opened from wileyhy:

Per `info uname,` `uname` always prints its data in the same order. Also, "note that A && B || C is not if-then-else. C may run when A is true." https://www.shellcheck.net/wiki/SC2015

set -x; read -r KERNEL_VERSION < <(uname -v); smp=x; [[ "$KERNEL_VERSION" = *SMP* ]] && { smp=y; readonly smp; false;} || smp=n; set -

Request URL : https://github.com/alsa-project/alsa-utils/pull/205 Patch URL : https://github.com/alsa-project/alsa-utils/pull/205.patch Repository URL: https://github.com/alsa-project/alsa-utils