clk: renesas: rcar-gen3: Rename DRIF clocks

According to the R-Car Gen3 Hardware Manual Errata for Rev. 1.50 of Feb
12, 2019, the DRIF clocks have been renamed as follows:

    DRIF0 to DRIF00
    DRIF1 to DRIF01
    DRIF2 to DRIF10
    DRIF3 to DRIF11
    DRIF4 to DRIF20
    DRIF5 to DRIF21
    DRIF6 to DRIF30
    DRIF7 to DRIF31

Therefore, this patch renames the DRIF clocks from DRIFn to DRIFmm.

Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>