LCD pins and onboard boot0 button annotations missing

[gsauthof]

The Longan Nana comes with a small LCD 160x80px display attached to a ST7735S controller.

Thus, some pins are occupied by this peripheral.

Namely some SPI0 pins and some controller pins.

The SPI0 pins are already marked in the pinout diagram.

However, the following LCD alternate function pins are missing:

BO -> RS
B1  -> RST
B2  -> CS

AFAICS, they are for command/data selection, reset and chip selection.

Ok, B2 isn't exposed as a pin, but could be included for completeness.

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The boot0 button is visible on the board image, but there is no marking that shows its connection:

It's connected to pin A8.

Adding this would arguably be useful to many since such a button is a popular target for first tests.