top: adjust some parenthesis for correct '^N' behavior

top: adjust some parenthesis for correct '^N' behavior

Some kdeinit tasks have a large environment consisting
mostly of nulls which were then followed by one or two
printable characters. Such strange environments should
not be shown with that 'not applicable' (n/a) notation
even though that first string vector is equal to '\0'.

I thought I had covered such a contingency but, due to
a misplaced right parenthesis, that '^N' bottom window
could see 'n/a' + a bunch of spaces + printable stuff.

Well, that won't happen anymore with this tiny change.

Signed-off-by: Jim Warner <james.warner@comcast.net>