Modified the techfile to make the cifoutput style "sky130(vendor)" the default,
since the prior default "sky130()" does not appear to be necessary or useful.
Added an alternative fill size 8 cell with diffusion on top and bottom which
acts as FOM fill.
diff --git a/sky130/magic/sky130.tech b/sky130/magic/sky130.tech
index ba24557..8757bd4 100644
--- a/sky130/magic/sky130.tech
+++ b/sky130/magic/sky130.tech
@@ -2299,7 +2299,7 @@
 # or else magic will scale below the allowed layout grid size
 #-----------------------------------------------------------------------
 
-style  sky130 variants (),(vendor)
+style  sky130 variants (vendor),()
  scalefactor 10 nanometers
  gridlimit 5