Heirloom Mailx hasn't been maintained for some time: the last release
on their web site was 11.25 in 2005 and Debian shipped 12.5 in 2016, but
this appears to be a Debian-specific fork which is also now dead.
Now that we have s-nail, we can drop mailx.
Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
e4ad5c15c3