Corrected an error in writing out .mag files with property values

that are longer than the formerly-fixed array size 256.  This
conflicted with the recent addition of holding path data in
properties, where the path coordinates can be significantly
longer than the fixed array size.  Same change as made to magic
version 8.1.

database/DBio.c

@@ -2455,10 +2455,12 @@ dbWritePropFunc(key, value, cdata)
     ClientData cdata;
 {
     FILE *f = (FILE *)cdata;
-    char lstring[256];
+    char *lstring;
 
+    lstring = (char *)mallocMagic(10 + strlen((char *)value) + strlen(key));
     sprintf(lstring, "string %s %s\n", key, (char *)value);
     FPRINTR(f, lstring);
+    freeMagic(lstring);
 
     return 0;
 }