Found a case where if no swap partition is set on linux, ptop will segfault when attempting to display that part of the header.  Now the header will simply not display any info.
Found a case where if no swap partition is set on linux, ptop will
segfault when attempting to display that part of the header.  Now
the header will simply not display any info.

markwkm/pg_top,mw2q/pg_top,mw2q/pg_top,mw2q/pg_top,markwkm/pg_top,markwkm/pg_top