ARM: dts: imx: Fix USB host power regulator polarity on M53Menlo

The MIC2025 switch input signal nEN is active low, describe it as such
in the DT. The previous change to this regulator polarity was incorrectly
influenced by broken quirks in gpiolib-of.c, which is now long fixed. So
fix this regulator polarity setting here once and for all.

Fixes: 3c3601cd ("ARM: dts: imx53: Update USB configuration on M53Menlo")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>