ARM: 8272/1: netx: Migrate DEBUG_LL macros to shared directory

As part of the migration we introduce DEBUG_UART_PHYS/DEBUG_UART_VIRT
which default to UART1 but allow a user to configure UART2 or UART3.
We also introduce symbolic names for the registers and flags.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>