ESP32S3 RPI_DPI_RGB component should allow "serial" RGB displays

[cocus]

Describe the problem you have/What new integration you would like
Current RPI_DPI_RGB component only makes use of parallel RGB displays, but there's also support from the IDF itself of the so-called "serial RGB" displays. Such displays use a parallel bus, but they require to latch the colors in separate clocks, for instance, an 8 bit bus that will provide the RED pixel data (8 bits), then the GREEN pixel data (another 8 bits), and finally the BLUE pixel data (another 8 bits), consuming 3 clocks per pixel. This works transparently for the user, since this is taken into account inside the IDF. In order to use this feature, when configuring the panel, the esp_lcd_rgb_panel_config_t structure should contain its member data_width set to a lower number than the bits_per_pixel member. For instance, data_width set to 8, while bits_per_pixel set to 24 (i.e. RGB888). This would mean you don't need to specify the red/green/blue pins separately, just the N pins used in the data_width.

Please describe your use case for this integration and alternatives you've tried:
A lot of LCD modules use this, and it's already implemented in IDF, so it's trivial to make use of.

Additional context
I'm using a A035QN05 display which is a 320*240, "serial RGB", with the following initialization code:

    esp_lcd_rgb_panel_config_t panel_config = {
        .data_width = 8, // RGB888
        .bits_per_pixel = 24,
        .num_fbs = 1,
        .dma_burst_size = 64,
        .clk_src = LCD_CLK_SRC_DEFAULT,
        .disp_gpio_num = -1,
        .pclk_gpio_num = GPIO_NUM_8,
        .vsync_gpio_num = GPIO_NUM_46,
        .hsync_gpio_num = GPIO_NUM_3,
        .de_gpio_num = -1,
        .data_gpio_nums = {
            GPIO_NUM_45,
            GPIO_NUM_21,
            GPIO_NUM_14,
            GPIO_NUM_13,
            GPIO_NUM_12,
            GPIO_NUM_11,
            GPIO_NUM_10,
            GPIO_NUM_9,
        },
        // The timing parameters should refer to your LCD spec
        .timings = {
            .pclk_hz = 27000000UL,
            .h_res = 320,
            .v_res = 240,

            .hsync_back_porch = 75,
            .hsync_front_porch = 686,
            .hsync_pulse_width = 1,

            .vsync_back_porch = 21,
            .vsync_front_porch = 2,
            .vsync_pulse_width = 1,
        },
        .flags.fb_in_psram = true,
    };

As you can see, there's not much deviation from a standard true "parallel" RGB display, just less pins declared, and the different values in data_width and bits_per_pixel

[cocus]

I figured that this would only apply when esp-idf v5.x is in use; this new parameter bits_per_pixel is not available on 4.x. For some reason, I can't make my ESP32S3 boot with esphome using 6.9.0 and idf 5.3.1; not sure why. I've tried a lot of things... In any case, I think it's beyond this point.

[cocus]

A concept can be found here: https://github.com/cocus/esphome/tree/cocus/rpi_rgb_serial. I think it might be improved greatly.