Incorrect bitbake syntax on dunfell branch

[mc-requtech]

The files recipes-kernel/linux/linux-altera-lts_5.10.bb and recipes-kernel/linux/linux-altera_5.13.bb in commit 237cd5e contains lines like

SRC_URI:append_cyclone5 = " file://lbdaf.scc "

which are not understood by bitbake 1.46. AFACT this syntax was introduced in bitbake 1.52. As such, this seems wrong for a branch called "dunfell" (since dunfell uses bitbake 1.46).