ARM: dts: renesas: replace toshiba, mmc-wrprotect-disable with disable-wp

Follow up commit 788778b0 ("mmc: tmio: deprecate "toshiba,
mmc-wrprotect-disable" DT property").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>