drivers: PL011: allow avoiding UART enabling/disabling
drivers: PL011: allow avoiding UART enabling/disabling

The SBSA UART should not be enabled or disabled (it is always on),
and consequently the spec lacks the UART_CR register.
Add a vendor specific property to skip disabling or enabling of the
UART. This will be used later by the SBSA UART support.

Signed-off-by: Andre Przywara <94eb15b8f54b8e37c3f8d338296201be47dc5c3e@arm.com>
Tested-by: Mark Langsdorf <eabffbbda805b4d9c4f51a24c4a43943d0f16369@redhat.com>
Tested-by: Naresh Bhat <df43eb7f02199d3013667256f41653ebdc08947d@cavium.com>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs