Corrected DNWELL layer generation in cifoutput;  the layer should
comprise "npn" instead of "pnp".

sky130/magic/sky130.tech

diff --git a/sky130/magic/sky130.tech b/sky130/magic/sky130.tech
index 8edca23..6d5eea6 100644
--- a/sky130/magic/sky130.tech
+++ b/sky130/magic/sky130.tech
@@ -747,7 +747,7 @@
 # DNWELL
 #----------------------------------------------------------------
 
- layer DNWELL	dnwell,pnp
+ layer DNWELL	dnwell,npn
 	calma	64 18
 
  layer PWRES    rpw