Makefile: Add GIT_BRANCH_* vars

Makefile

@@ -38,6 +38,12 @@ BUILD_TARGET_sysmocom-alix = "core-image-minimal-initramfs meta-toolchain-osmo t
 # approiate here or not.
 BUILD_TARGETS="$(BUILD_TARGET_$(CUR_MACHINE))"
 
+GIT_BRANCH_POKY		= "$(POKY_RELEASE)"
+GIT_BRANCH_SYSMOCOM_BSP = "$(SYSMOCOM_RELEASE)"
+GIT_BRANCH_TELEPHONY	= "$(SYSMOCOM_RELEASE)"
+GIT_BRANCH_SMALLTALK	= "$(SYSMOCOM_RELEASE)"
+GIT_BRANCH_QT5		= "$(SYSMOCOM_RELEASE)"
+
 #
 usage:
 	@echo "Pick a target like help, update or sysmocom-alix-setup"
@@ -66,8 +72,9 @@ help:
 	@echo " make-server-structure	- Create directories for machine/release"
 	@echo "Available variables:"
 	@echo " V=1			- Enable verbose command output"
-	@echo " SYSMOCOM_RELEASE=name	- Pick branch during clone"
-	@echo " POKY_RELEASE=name	- Pick branch during clone"
+	@echo " SYSMOCOM_RELEASE=name	- Pick release branch during clone"
+	@echo " POKY_RELEASE=name	- Pick release branch during clone"
+	@echo " GIT_BRANCH_*		- Pick branch for a specific repository"
 
 # Fetch/update all repos... Expand REPOS and append -update to the rule
 # e.g. poky-update meta-telephony-update
@@ -85,15 +92,15 @@ git:
 
 ## Clone repositories. The other option is by variable something like BRNACH_poky, REPO_poky
 git/poky: | git
-	$(V)cd git && git clone --branch=$(POKY_RELEASE) --depth=1 git://git.yoctoproject.org/poky
+	$(V)cd git && git clone --branch=$(GIT_BRANCH_POKY) --depth=1 git://git.yoctoproject.org/poky
 git/meta-sysmocom-bsp: | git
-	cd git && git clone --branch=$(SYSMOCOM_RELEASE) git://git.sysmocom.de/poky/meta-sysmocom-bsp
+	cd git && git clone --branch=$(GIT_BRANCH_SYSMOCOM_BSP) git://git.sysmocom.de/poky/meta-sysmocom-bsp
 git/meta-telephony: | git
-	cd git && git clone --branch=$(SYSMOCOM_RELEASE) git://git.osmocom.org/meta-telephony
+	cd git && git clone --branch=$(GIT_BRANCH_TELEPHONY) git://git.osmocom.org/meta-telephony
 git/meta-smalltalk: | git
-	cd git && git clone --branch=$(SYSMOCOM_RELEASE) git://github.com/sysmocom/meta-smalltalk
+	cd git && git clone --branch=$(GIT_BRANCH_SMALLTALK) git://github.com/sysmocom/meta-smalltalk
 git/meta-qt5: | git
-	cd git && git clone --branch=$(SYSMOCOM_RELEASE) git://github.com/sysmocom/meta-qt5
+	cd git && git clone --branch=$(GIT_BRANCH_QT5) git://github.com/sysmocom/meta-qt5
 
 ## Create a build directory, e.g. build.sysmobts
 ## Use Poky to set-up the directory and then customize it. Copy files