ANDROID: serial: msm_geni_serial_console : Add Earlycon support

This change enables earlyconsole support as static driver for geni
based UART. Kernel space UART console driver will be generic for
console and other usecases of UART.

Bug: 144074026
Test: Earlyconsole logs are fine and switch kernel console is fine.

Change-Id: I34c9910cc8aa9586f842362fae62bc7127bcee5e
Signed-off-by: Mukesh Kumar Savaliya <msavaliy@codeaurora.org>
(cherry picked from commit ac0ec822779819c8d5cdc1d97d44afdefe1d3ece)
Signed-off-by: Will McVicker <willmcvicker@google.com>