devtool: standard: Expand SRCREV before using it in _update_recipe_srcrev
If SRCREV contains a variable reference, any devtool command that
would try to update it would fail. E.g., if SRCREV = "R${PV}", then
devtool finish without having committed any changes would fail with:
oe.patch.CmdError: Command Error: 'sh -c 'git format-patch R${PV} -o
/tmp/oepatchb_doareb -- .'' exited with 0 Output:
fatal: bad revision 'R'
Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
