arm64: defconfig: Enable additional support for Renesas platforms

Increase build and test coverage by enabling support for more hardware
present on Renesas SoCs and boards:
  - Renesas RZ/V2M I2C,
  - Renesas Universal Flash Storage Controller on R-Car S4, as used on
    the Spider board.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/bd863fdd098be394d57b9dc15f8bb0f6b1f2d78a.1661162345.git.geert+renesas@glider.be