makefile: Fix target install

These lines should be tabs not spaces

Change-Id: Ibaceacd88968d73fed8403dcd9278dc071415ebc
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/Makefile.am b/Makefile.am
index ec1dfaf..5e06d0c 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,8 +2,8 @@
 
 if HAVE_SYSTEMD
 systemdsystemunit_DATA = \
-  gbmc-psu-hardreset.target \
-  gbmc-host-poweroff.target
+	gbmc-psu-hardreset.target \
+	gbmc-host-poweroff.target
 endif
 
 # Ignore system headers