vsh-table: allow empty columns

Trivially implement this by deleting the bogus check in
vshTableSafeEncode.

Now it returns an empty string for an empty string instead
of returning NULL without setting an error.

Signed-off-by: Ján Tomko <jtomko@redhat.com>

tools/vsh-table.c

@@ -219,9 +219,6 @@ vshTableSafeEncode(const char *s, size_t *width)
 
     memset(&st, 0, sizeof(st));
 
-    if (!sz)
-        return NULL;
-
     if (VIR_ALLOC_N(buf, (sz * HEX_ENCODE_LENGTH) + 1) < 0)
         return NULL;