It is silly to bury UART selection under multiple levels of choice
statements, where the top level choice statement will only list
about four entries when a single SoC is selected.  Move the UART
selection up into the top level choice statement as it was always
intended to be.
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>