grub-efi.bbclass: make it can build vm and live together

* Make it can build vm and live (e.g., iso + vmdk) together as we did
  for syslinux.
* GRUBCFG -> GRUB_CFG as other GRUB_FOO vars

(From OE-Core rev: e38039e43f22d55a443064efa91752e2943fda79)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/grub-efi.bbclass

@@ -19,7 +19,8 @@ do_bootimg[depends] += "${MLPREFIX}grub-efi:do_deploy"
 do_bootdirectdisk[depends] += "${MLPREFIX}grub-efi:do_deploy"
 
 GRUB_SERIAL ?= "console=ttyS0,115200"
-GRUBCFG = "${S}/grub.cfg"
+GRUB_CFG_VM = "${S}/grub_vm.cfg"
+GRUB_CFG_LIVE = "${S}/grub_live.cfg"
 GRUB_TIMEOUT ?= "10"
 #FIXME: build this from the machine config
 GRUB_OPTS ?= "serial --unit=0 --speed=115200 --word=8 --parity=no --stop=1"
@@ -43,7 +44,7 @@ efi_populate() {
 	fi
 	install -m 0644 ${DEPLOY_DIR_IMAGE}/${GRUB_IMAGE} ${DEST}${EFIDIR}
 
-	install -m 0644 ${GRUBCFG} ${DEST}${EFIDIR}/grub.cfg
+	install -m 0644 ${GRUB_CFG} ${DEST}${EFIDIR}/grub.cfg
 }
 
 efi_iso_populate() {
@@ -83,9 +84,9 @@ python build_efi_cfg() {
         bb.debug(1, "No labels, nothing to do")
         return
 
-    cfile = d.getVar('GRUBCFG', True)
+    cfile = d.getVar('GRUB_CFG', True)
     if not cfile:
-        raise bb.build.FuncFailed('Unable to read GRUBCFG')
+        raise bb.build.FuncFailed('Unable to read GRUB_CFG')
 
     try:
          cfgfile = file(cfile, 'w')

meta/classes/image.bbclass

@@ -543,7 +543,7 @@ addtask bundle_initramfs after do_image_complete
 # Some of the vars for vm and live image are conflicted, this function
 # is used for fixing the problem.
 def set_live_vm_vars(d, suffix):
-    vars = ['SYSLINUX_CFG', 'ROOT', 'LABELS', 'INITRD']
+    vars = ['GRUB_CFG', 'SYSLINUX_CFG', 'ROOT', 'LABELS', 'INITRD']
     for var in vars:
         var_with_suffix = var + '_' + suffix
         if d.getVar(var, True):