tbb: enable building with non-Apple compilers

Closes #25366.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
zsh: fix --enable-etcdir

`--enable-etcdir` becomes `--enable-etcdir=/etc`

Fixes #25391.
Closes #25392.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>