Tweak density

Author: MichaelBell

src/config.json

@@ -13,7 +13,7 @@
 
   "//": "PL_TARGET_DENSITY_PCT - You can increase this if Global Placement fails with error GPL-0302.",
   "//": "Users have reported that values up to 80 worked well for them.",
-  "PL_TARGET_DENSITY_PCT": 64.2,
+  "PL_TARGET_DENSITY_PCT": 64,
 
   "//": "CLOCK_PERIOD - Increase this in case you are getting setup time violations.",
   "//": "The value is in nanoseconds, so 20ns == 50MHz.",