arm: configs: zynq_pluto_defconfig: Enable ext4 filesystem support

This allows swith_root or chroot'ers to use a real file system on a USB
drive.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>

Author: mhennerich

arch/arm/configs/zynq_pluto_defconfig

@@ -246,6 +246,7 @@ CONFIG_XILINX_XADC=y
 CONFIG_CF_AXI_DDS=y
 CONFIG_FPGA=y
 CONFIG_FPGA_MGR_ZYNQ_FPGA=y
+CONFIG_EXT4_FS=y
 # CONFIG_DNOTIFY is not set
 CONFIG_MSDOS_FS=y
 CONFIG_VFAT_FS=y