payloads/tianocore: remove single branch checkout parameter

using '--single-branch' when cloning the tianocore repo
prevents the use of other branches/commits outside of the
checked-out coreboot_fb branch, so remove it.

Test: build with TIANOCORE_REVISION selected and revision
set to origin/master, verify checkout succeeds

Change-Id: If8c93aa87957ba2ff9ab7a58e84d2a25b48ec346
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/31686
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/payloads/external/tianocore/Makefile b/payloads/external/tianocore/Makefile
index 06e8b68..2c7439c 100644
--- a/payloads/external/tianocore/Makefile
+++ b/payloads/external/tianocore/Makefile
@@ -48,7 +48,7 @@
 
 $(project_dir):
 	echo "    Cloning $(project_name) from Git"
-	git clone --single-branch --branch $(project_git_branch) $(project_git_repo) $(project_dir); \
+	git clone --branch $(project_git_branch) $(project_git_repo) $(project_dir); \
 		cd $(project_dir); \
 		git remote add upstream $(upstream_git_repo)