configs/qemu_aarch64_virt_defconfig: don't hard code getty port

The Linux defconfig both has VT and serial port support, so it makes more
sense to run getty on /dev/console instead of hard coding the serial port.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

configs/qemu_aarch64_virt_defconfig

@@ -4,7 +4,6 @@ BR2_cortex_a53=y
 
 # System
 BR2_SYSTEM_DHCP="eth0"
-BR2_TARGET_GENERIC_GETTY_PORT="ttyAMA0"
 
 # Filesystem
 BR2_TARGET_ROOTFS_EXT2=y