microblaze: defconfig: Enable devtmps and tmpfs

Currently dropbear does not run in background because devtmps and tmpfs
is not enabled by default. Enable devtmps and tmpfs to fix this issue.
Signed-off-by: Manjukumar Matha <manjukumar.harthikote-matha@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/microblaze/configs/mmu_defconfig

@@ -33,6 +33,8 @@ CONFIG_INET=y
 # CONFIG_IPV6 is not set
 CONFIG_BRIDGE=m
 CONFIG_PCI=y
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
 CONFIG_MTD=y
 CONFIG_MTD_CFI=y
 CONFIG_MTD_CFI_INTELEXT=y
@@ -73,6 +75,7 @@ CONFIG_UIO_PDRV_GENIRQ=y
 CONFIG_UIO_DMEM_GENIRQ=y
 CONFIG_EXT2_FS=y
 # CONFIG_DNOTIFY is not set
+CONFIG_TMPFS=y
 CONFIG_CRAMFS=y
 CONFIG_ROMFS_FS=y
 CONFIG_NFS_FS=y