Move tacoma over to standard phosphor-image

witherspoon-tacoma is now being built with the standard flash
layout for 128mb OpenBMC systems

Change-Id: Ie2fe2256197546a993323a010465ba3ff094d3e1
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/build-setup.sh b/build-setup.sh
index c432946..08f4cae 100755
--- a/build-setup.sh
+++ b/build-setup.sh
@@ -156,7 +156,6 @@
     LAYER_DIR="meta-ibm/meta-witherspoon"
     MACHINE="witherspoon-tacoma"
     DISTRO="openbmc-openpower"
-    bitbake_target="aspeed-image-norootfs"
     ;;
   rainier)
     LAYER_DIR="meta-ibm/meta-witherspoon"