vexpress64: use DM for all vexpress64 boards

Commit d8bafe1310487ba0e0785997726b4792072178d3
"ARMv8: enable DM in vexpress64 board" only enabled DM
for the simulated vexpress64 board (FVP) with the
hardcoded clock value for the simulated board, causing
a console regression on the Juno board which was using
a different clock setting.

Fix this by enabling DM for all vexpress64 boards,
defining the clock frequency per-board, deleting the
static array of PL01x ports from the config file and
relying solely on the port defined in the boardfile
using platform data.

Cc: David Feng <fenghua@phytium.com.cn>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/board/armltd/vexpress64/vexpress64.c b/board/armltd/vexpress64/vexpress64.c
index 13dd667..7cb4e00 100644
--- a/board/armltd/vexpress64/vexpress64.c
+++ b/board/armltd/vexpress64/vexpress64.c
@@ -19,7 +19,7 @@
 static const struct pl01x_serial_platdata serial_platdata = {
 	.base = V2M_UART0,
 	.type = TYPE_PL011,
-	.clock = 2400 * 1000,
+	.clock = CONFIG_PL011_CLOCK,
 };
 
 U_BOOT_DEVICE(vexpress_serials) = {