arm: mvebu: Don't use CONFIG_TIMER on ARM64

The 64-bit mvebu SoCs don't have a suitable timer driver so add a !ARM64
condition to the select.

Fixes: 7b530bb19e ("arm: mvebu: Use CONFIG_TIMER on all MVEBU & KIRKWOOD platforms")
Signed-off-by: Chris Packham <judge.packham@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>

arch/arm/Kconfig

@@ -640,7 +640,7 @@ config ARCH_MVEBU
 	select SPL_DM_SPI if SPL
 	select SPL_DM_SPI_FLASH if SPL
 	select SPL_TIMER if SPL
-	select TIMER
+	select TIMER if !ARM64
 	select OF_CONTROL
 	select OF_SEPARATE
 	select SPI