ARM: shmobile: ape6evm dts: Drop console= bootargs parameter

Since ("ARM: shmobile: r8a73a4: ape6evm: Remove legacy platform"),
ape6evm is restricted to booting from DT, so chosen/stdout-path is
always used, and we can drop the "console=" parameter from
chosen/bootargs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>