security/intel/cbnt/Makefile: Fix invalid char '*'

It seems that using a wildcard (*) in the import path is not supported
in the context of the Makefile.
This to fix this error:
  malformed import path "cmd/cbnt-prov/*.go": invalid char '*'

Change-Id: I953e06f1ff70a2b61bc5f505f7df9936b7f9b55b
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75638
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
diff --git a/src/security/intel/cbnt/Makefile.inc b/src/security/intel/cbnt/Makefile.inc
index 4959f01..4c585b8 100644
--- a/src/security/intel/cbnt/Makefile.inc
+++ b/src/security/intel/cbnt/Makefile.inc
@@ -34,7 +34,7 @@
 $(CBNT_PROV):
 	printf "    CBNT_PROV    building tool\n"
 	cd 3rdparty/intel-sec-tools; \
-	GO111MODULE=on go build -o $(abspath $@) cmd/cbnt-prov/*.go
+	GO111MODULE=on go build -o $(abspath $@) cmd/cbnt-prov/main.go cmd/cbnt-prov/cmd.go
 else
 $(CBNT_PROV): $(call strip_quotes, $(CONFIG_INTEL_CBNT_PROV_EXTERNAL_BIN_PATH))
 	cp $< $@