net/tsocks: Fix erroneous substitution

When patching the wrapper script for /usr to ${PREFIX} a part in a sed
statement gets substituted that should be escaped. Adjust sed statement
in a way that it doesn't break after patching ${PREFIX}.

While here:

• move a REINPLACE_CMD operation to a pre-existing patch file
• pacify portclippy
• reformat with portfmt

PR: 267670
Reported by: chris@mumac.de