Half-fix for giza paper size error.

Fixes these errors:
%giza - ERROR - giza_set_paper_size: width <= 0
%giza - ERROR - giza_set_paper_size: height <= 0

But the size is still too small, and a bit worse...

	modified:   skymap.c

skymap.c

@@ -959,7 +959,7 @@ void init_plot(char *psfile,float width,float aspect)
   // Initialize plot
   cpgopen(psfile);
   cpgslw(2);
-  cpgpap(width,aspect);
+  cpgpap(7.5,1);
 
   skymap_plot_renew();