futility: stop using the symlink names in utility scripts

We still create the symlinks (FOO -> futility), but this
change invokes those built-in functions with "futility FOO ..."
instead of using the FOO symlink.

Note that the scripts/ directory is unchanged. That's a
separate CL, since we don't have tests for that.

BUG=chromium:231547
BRANCH=ToT
TEST=make runtests

In addition to running "make runtests", I temporarily
modified the Makefile to avoid creating the symlinks at all.
The tests still passed.

Change-Id: I96863259b9df02a3611f759a7509bf4090ae03e8
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/216717
Reviewed-by: Randall Spangler <rspangler@chromium.org>
diff --git a/Makefile b/Makefile
index f8572db..371ba8b 100644
--- a/Makefile
+++ b/Makefile
@@ -520,7 +520,7 @@
 # These are the executables that are now built in to futility. We'll create
 # symlinks for these so the old names will still work.
 # TODO: Do we still need dev_sign_file for anything?
-FUTIL_BUILTIN = \
+FUTIL_SYMLINKS = \
 	dev_sign_file \
 	dump_fmap \
 	dump_kernel_config \
@@ -901,7 +901,7 @@
 	@$(PRINTF) "    INSTALL       futility\n"
 	${Q}mkdir -p ${UB_DIR}
 	${Q}${INSTALL} -t ${UB_DIR} ${FUTIL_BIN} ${FUTIL_STATIC_BIN}
-	${Q}for prog in ${FUTIL_BUILTIN}; do \
+	${Q}for prog in ${FUTIL_SYMLINKS}; do \
 		ln -sf futility "${UB_DIR}/$$prog"; done
 
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