free: Fix first column justification

free: Fix first column justification

free has for many years had a problem with translated header columns
or the first column. This is because printf("-9s", str) doesn't use
the wide length of the string but the char length meaning they are
mis-aligned.

Using the mbstowcs() function to get the wide length and then
a precision parameter to append the right number of spaces after the
number means we get what we need.

References:
 procps-ng/procps#229
 procps-ng/procps#204
 procps-ng/procps#206
 https://bugs.debian.org/1001689

Signed-off-by: Craig Small <csmall@dropbear.xyz>