util/testing: Remove amdfwread from makefile

amdfwread was added to the testing makefile but ended up not becoming a
separate tool. This commit removes it from the makefile so that `make
distclean` works again.

Fixes: 29bc79fddb62c30caa33474ac773ae6a6ec1c4f0 ("util/amdfwtool: Add
amdfwread utility")

TEST=Ran `make distclean`

Signed-off-by: Robert Zieba <robertzieba@google.com>
Change-Id: I2c8b920bc69d6c20558a28515c52a1e9cecebe27
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64348
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/util/testing/Makefile.inc b/util/testing/Makefile.inc
index 5a81e3b..5c9e4d8 100644
--- a/util/testing/Makefile.inc
+++ b/util/testing/Makefile.inc
@@ -50,7 +50,6 @@
 	echo
 
 TOOLLIST= \
-amdfwread \
 amdfwtool \
 cbfstool \
 cbmem \