clk: renesas: rzg2l: Fix intin variable size

clk: renesas: rzg2l: Fix intin variable size

INTIN is a 12-bit register value, so u8 is too small.

Fixes: 1561380ee72f ("clk: renesas: rzg2l: Add FOUTPOSTDIV clk support")
Cc: stable@vger.kernel.org
Reported-by: Hugo Villeneuve <hugo@hugovil.com>
Closes: https://lore.kernel.org/20251107113058.f334957151d1a8dd94dd740b@hugovil.com
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20251114193711.3277912-1-chris.brandt@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>