stop statically linking crossystem

Now that initramfs, firmware updater, and auto-updater are all using
dynamically linked programs, there's no need to produce a static
build of crossystem anymore.

BUG=chromium:765499
TEST=precq passes (includes vmtests w/AU)
BRANCH=None

Change-Id: I5aa123e662040ff5d9f2328c0f036b648fc629fb
Reviewed-on: https://chromium-review.googlesource.com/667881
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>

Author: vapier

Makefile

@@ -594,11 +594,10 @@ UTIL_SCRIPTS += \
 endif
 
 # These utilities should also provide static linked version (*_s).
-UTIL_NAMES_STATIC = \
-	utility/crossystem
+UTIL_NAMES_STATIC =
 
 UTIL_NAMES = \
-	${UTIL_NAMES_STATIC} \
+	utility/crossystem \
 	utility/dumpRSAPublicKey \
 	utility/tpmc