armv8: ls1088a: Unset USE_BOOTCOMMAND in defconfig

Unset USE_BOOTCOMMAND for all ls1088 defconfig files to fix
redefinition error. USE_BOOTCOMMAND was introduced in commit
b6251db8c3f ("Kconfig: Introduce USE_BOOTCOMMAND and migrate
BOOTCOMMAND").

Signed-off-by: Ashish Kumar <Ashish.Kumar@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/configs/ls1088ardb_qspi_defconfig b/configs/ls1088ardb_qspi_defconfig
index 1f3d581..bb5e72c 100644
--- a/configs/ls1088ardb_qspi_defconfig
+++ b/configs/ls1088ardb_qspi_defconfig
@@ -9,6 +9,7 @@
 CONFIG_OF_STDOUT_VIA_ALIAS=y
 CONFIG_SYS_EXTRA_OPTIONS="SYS_FSL_DDR4, QSPI_BOOT"
 # CONFIG_DISPLAY_BOARDINFO is not set
+# CONFIG_USE_BOOTCOMMAND is not set
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_I2C=y
 CONFIG_CMD_MMC=y