linux-raspberrypi.inc: Change defconfig for RPi3 64 bits

Switch to bcm2711_defconfig for RPi3 64 bits as per
https://github.com/raspberrypi/linux/pull/6688

Signed-off-by: Florin Sarbu <florin@balena.io>

recipes-kernel/linux/linux-raspberrypi.inc

@@ -28,7 +28,7 @@ KBUILD_DEFCONFIG:raspberrypi ?= "bcmrpi_defconfig"
 KBUILD_DEFCONFIG:raspberrypi-cm3 ?= "bcm2709_defconfig"
 KBUILD_DEFCONFIG:raspberrypi2 ?= "bcm2709_defconfig"
 KBUILD_DEFCONFIG:raspberrypi3 ?= "bcm2709_defconfig"
-KBUILD_DEFCONFIG:raspberrypi3-64 ?= "bcmrpi3_defconfig"
+KBUILD_DEFCONFIG:raspberrypi3-64 ?= "bcm2711_defconfig"
 KBUILD_DEFCONFIG:raspberrypi4 ?= "bcm2711_defconfig"
 KBUILD_DEFCONFIG:raspberrypi4-64 ?= "bcm2711_defconfig"
 KBUILD_DEFCONFIG:raspberrypi-armv7 ?= "bcm2711_defconfig"