Config-devel.in: rename symbol KERNEL_GIT_BRANCH -> KERNEL_GIT_REF

The Download/git rule will do a `git checkout <git-ref>`.
So, we can use any ref we want.

No need to limit just to branches.

Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>

config/Config-devel.in

@@ -90,13 +90,14 @@ menuconfig DEVEL
 		  In this instance, the --reference option of git clone will
 		  be used thus creating a quick local clone of your repo.
 
-	config KERNEL_GIT_BRANCH
-		string "Enter git branch to clone" if DEVEL
+	config KERNEL_GIT_REF
+		string "Enter git ref at which to checkout" if DEVEL
 		depends on (KERNEL_GIT_CLONE_URI != "")
 		default ""
 		help
-		  Enter the branch name to checkout after cloning the git repository.
-		  In this instance, the --branch option of git clone will be used.
+		  Enter the git ref at which to checkout the git repository
+		  after it is cloned, and before making it a tar-ball.
+		  It can be a git hash or a branch name.
 		  If unused, the clone's repository HEAD will be checked-out.
 
 	config BUILD_LOG

include/kernel-build.mk

@@ -50,14 +50,10 @@ ifneq ($(strip $(CONFIG_KERNEL_GIT_LOCAL_REPOSITORY)),"")
   KERNEL_GIT_OPTS+=--reference $(CONFIG_KERNEL_GIT_LOCAL_REPOSITORY)
 endif
 
-ifneq ($(strip $(CONFIG_KERNEL_GIT_BRANCH)),"")
-  KERNEL_GIT_OPTS+=--branch $(CONFIG_KERNEL_GIT_BRANCH)
-endif
-
 define Download/git-kernel
   URL:=$(call qstrip,$(CONFIG_KERNEL_GIT_CLONE_URI))
   PROTO:=git
-  VERSION:=$(CONFIG_KERNEL_GIT_BRANCH)
+  VERSION:=$(CONFIG_KERNEL_GIT_REF)
   FILE:=$(LINUX_SOURCE)
   SUBDIR:=linux-$(LINUX_VERSION)
   OPTS:=$(KERNEL_GIT_OPTS)