ghc: enable unregisterised builds on armhf. This is mainly done for Ubuntu,...

ghc: enable unregisterised builds on armhf. This is mainly done for Ubuntu, were we gain from building ghc itself in 2.5 days and more, to 2.5 hours.
This can be done also in Ubuntu only, but I'm pretty confident this performance gain can be beneficial in Debian too

p/ghc/debian/rules

@@ -39,7 +39,7 @@ export GHC=$(firstword $(shell bash -c "type -p ghc"))
 
 DEB_HOOGLE_TXT_DIR = /usr/lib/ghc-doc/hoogle/
 
-ifneq (,$(filter i386 powerpcspe x32 s390x, $(DEB_HOST_ARCH)))
+ifneq (,$(filter armhf i386 powerpcspe x32 s390x, $(DEB_HOST_ARCH)))
   # From GHC 8.10 and later, native code generator support for legacy x87
   # floating point coprocessor has been removed. GHC now only support floating
   # point via SSE2. This causes a baseline violation on Debian for i386 where