pinctrl: renesas: r8a779g0: Fix Group 4/5 pin functions

According to R-Car V4H Series User’s Manual: Hardware Rev. 0.54, pin
groups 4 and 5 do not use Module Select Registers to configure pin
functions, but use Peripheral Function Select Registers instead.

Hence:
  - Remove the non-existent Module Select Registers (MODSEL[45]),
  - Add the missing Peripheral Function Select Registers (IPxSR[45]),
  - Correct the GPIO / Peripheral Function Select Register definitions
    (GPSR]45_*),
  - Correct the affected PINMUX definitions.

Fixes: 36611d28 ("pinctrl: renesas: r8a779g0: Add missing MODSELx for AVBx")
Fixes: 36fb7b8a ("pinctrl: renesas: r8a779g0: Add missing MODSELx for TSN0")
Fixes: ad9bb2fe ("pinctrl: renesas: Initial R8A779G0 (R-Car V4H) PFC support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/3d3833d1738f5e8fcc4c1002aa93832464d129a0.1669036423.git.geert+renesas@glider.be