Fix configuration error due to undefined conditionals

If AM_CONDITIONAL is run conditionally, it needs to be run for every
condition. If not, it will cause errors.

Issue: https://github.com/openbmc/phosphor-ipmi-flash/issues/8

Signed-off-by: Vivekanand Veeracholan <vveerach@google.com>
Change-Id: I015686e795cb8d4491c839d822e9748cbac0dacb
diff --git a/configure.ac b/configure.ac
index 7747b76..b2cf20c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -138,6 +138,8 @@
     ])
 ], [
     AM_CONDITIONAL([ENABLE_HOST_BIOS], [0])
+    AM_CONDITIONAL([HAVE_SYSTEMUNITDIR], [0])
+    AM_CONDITIONAL([HAVE_TMPFILESDIR], [0])
 ])
 
 # If not building the host-tool, we're building the BMC.