pinctrl: renesas: rzg2l: Index all registers based on port offset

To get the address that needs to be read/written for specific port
functionalities, the P(), PM(), PMC(), PFC(), PIN(), IOLH() IEN(),
ISEL() macros are used.  Some of these macros receive as argument the
hardware port identifier, some the hardware port offset address (e.g.
ISEL() received port identifier, IOLH() received port offset address).
This makes it hard to extend the current driver for SoCs where port
identifiers are not contiguous in the memory map of the pin controller.
This is the case for the RZ/G3S pin controller where ports are mapped as
follows:

    port offset    port identifier
    -----------    ---------------
    0x20           P0
    0x21           P5
    0x22           P6
    0x23           P11
    0x24           P12
    0x25           P13
    0x26           P14
    0x27           P15
    0x28           P16
    0x29           P17
    0x2a           P18
    0x30           P1
    0x31           P2
    0x32           P3
    0x33           P4
    0x34           P7
    0x35           P8
    0x36           P8
    0x37           P10

To make this achievable, change all the above macros used to get the
address of a port register for a specific port functionality based on
the port hardware address.  Summarized, all the above macros will get as
argument the port offset address listed in the above table.

With this RZG2L_SINGLE_PIN_GET_PORT_OFFSET(),
RZG2L_PIN_ID_TO_PORT_OFFSET() and RZG2L_GPIO_PORT_GET_INDEX() were
replaced by RZG2L_PIN_CFG_TO_PORT_OFFSET(); RZG2L_SINGLE_PIN_GET_CFGS()
and RZG2L_GPIO_PORT_GET_CFGS() were replaced by RZG2L_PIN_CFG_TO_CAPS().

Also rzg2l_pinctrl_set_pfc_mode() does not need the port argument
anymore.  Also rzg2l_gpio_direction_input() and
rzg2l_gpio_direction_output() do not need to translate port and bit
locally as this can be done by rzg2l_gpio_set_direction().

To use the same naming for port, bit/pin, and register offset, replace
the port_offset variable names in different places by variables named
off.  There is no longer a need to initialize cfg and bit in different
code places.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20230929053915.1530607-15-claudiu.beznea@bp.renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>