Corrected the Makefile, which was using the "exclude" option on the
standard cell verilog that was supposed to be used on the standard
cell LEF.  Mostly all this does is to change the nature of the error
that occurs.  Ultimately the source of the LEF files needs to be
fixed, which will happen eventually.  Also corrected the generate()
routine in soc_floorplanner.  This fixes the behavior in which
clicking on the "Generate" button in the floorplanner app causes
an error.
diff --git a/common/soc_floorplanner.py b/common/soc_floorplanner.py
index 959a623..31c6b8f 100755
--- a/common/soc_floorplanner.py
+++ b/common/soc_floorplanner.py
@@ -260,7 +260,7 @@
         self.vlogimport()
         self.readplacement(precheck=True)
         self.resolve()
-        self.generate(0)
+        self.generate()
 
     # Local routines for handling printing to the text console
 
@@ -525,7 +525,7 @@
         # position;  corners are fixed by definition.
         if padrow == self.NEpad or padrow == self.SEpad or padrow == self.SWpad or padrow == self.NWpad:
             # Easier to run generate() than to put the pad back. . .
-            self.generate(0)
+            self.generate()
             return
 
         # Find the original center point of the pad being moved
@@ -656,7 +656,7 @@
             rowbefore.insert(idx, pad)
 
         # Re-run padring
-        self.generate(0)
+        self.generate()
 
     def on_scrollwheel(self, event):
         if event.num == 4:
@@ -1923,7 +1923,7 @@
     # Generate a new padframe by writing the configuration file, running
     # padring, reading back the DEF file, and (re)poplulating the workspace
 
-    def generate(self, level):
+    def generate(self, level=0):
         self.print('Generate legal padframe using padring')
 
         # Write out the configuration file