BCM2711: AUX_MU_LCR_REG Data size field is wrong

[alloncm]

The latest BCM2711 peripherals docs is wrong about the data size parameter.

According to this errata for BCM2835, bit 1 also must be set for 8 bit mode (and not just bit 0 as the docs says). I tested this on my RPi4 and also checked the Linux kernel headers and saw that this parameter is 2 bits wide and contains also options for Data size of 5 and 6 (which the docs never mention).

Thanks!