pinctrl: sh-pfc: r8a7795: Rename SSI_{WS,SCK}34 to SSI_{WS,SCK}349

R-Car Gen3 is using SSI_{WS,SCK}349 instead of SSI_{WS,SCK}34.
But, current code is based on old datasheet which had typo.
This patch fixes this typo.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>