Documentation: fsl-quadspi: Add fsl, imx7d-qspi compatible string
Documentation: fsl-quadspi: Add fsl, imx7d-qspi compatible string

new compatible string: "fsl,imx7d-qspi"

Signed-off-by: Frank Li <d9a81cb4fa8b4f356eefd38684e2f43f08dbec49@freescale.com>
Signed-off-by: Brian Norris <ac73eed4b8a8c9127255a2696c52b2e7503720b8@gmail.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs