configs: versal: Enable CONFIG_LTO for mini qspi/ospi

Adding a tiny bit more code for mini u-boot leads to a OCM
image overflow. Fix this by enabling LTO for this board, so that such
changes still can be made to the common U-Boot code.

Enable building mini u-boot image with LTO, which results in about 8KB
reduction in size.

Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@amd.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20240126080900.3209323-1-venkatesh.abbarapu@amd.com
diff --git a/configs/xilinx_versal_mini_ospi_defconfig b/configs/xilinx_versal_mini_ospi_defconfig
index 72a123d..7a11035 100644
--- a/configs/xilinx_versal_mini_ospi_defconfig
+++ b/configs/xilinx_versal_mini_ospi_defconfig
@@ -16,6 +16,7 @@
 CONFIG_VERSAL_NO_DDR=y
 # CONFIG_PSCI_RESET is not set
 CONFIG_SYS_LOAD_ADDR=0x8000000
+CONFIG_LTO=y
 # CONFIG_EXPERT is not set
 CONFIG_REMAKE_ELF=y
 # CONFIG_AUTOBOOT is not set