arm64: dts: freescale: imx8-ss-lsio: Fix flexspi clock order

The correct clock order is "fspi_en" and "fspi". As they are identical
just reordering the names is sufficient.

Fixes: 6276d669 ("arm64: dts: imx8dxl: add flexspi0 support")
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>