mtd:spi-nor: Added generic gqspi driver for ZynqMP

Added the basic io version of gqspi driver.
Added entry for gqspi driver in kconfig and makefile.

Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

qs