ARM: 7793/1: debug: use generic option for ep93xx PL10x debug port

The generic option DEBUG_LL_UART_PL01X is now used to select the UART
type for the kernel low-level debugging on the ep93xx platform. This
enables two config options to provide the physical and virtual base
address of the debug UART.

Use the generic options instead of providing platform specific options
to select the debug UART.

UART1 is selected with:  DEBUG_UART_PHYS = 0x808c0000
                         DEBUG_UART_VIRT = 0xfedc0000

UART2 is selected with:  DEBUG_UART_PHYS = 0x808d0000
                         DEBUG_UART_VIRT = 0xfedd0000

UART3 is selected with:  DEBUG_UART_PHYS = 0x808e0000
                         DEBUG_UART_VIRT = 0xfede0000

The selected UART must already be initialized by the bootloader. If it
isn't setup nothing will appear (which might be desired).

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>