uboot-imx

sf: Update status reg check in spi_flash_cmd_wait_ready

Current flash wait_ready logic is not modular to add new
register status check, hence updated the status check for
adding few more register checks in future.

Below are the sf speed runs with 'sf update' on whole flash, 16MiB.

=> sf update 0x100 0x0 0x1000000
device 0 whole chip
16777216 bytes written, 0 bytes skipped in 59.564s, speed 289262 B/s

=> sf update 0x100 0x0 0x1000000
device 0 whole chip
16777216 bytes written, 0 bytes skipped in 62.549s, speed 275036 B/s

=> sf update 0x100 0x0 0x1000000
device 0 whole chip
16777216 bytes written, 0 bytes skipped in 61.276s, speed 284359 B/s

Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Tom Warren <twarren@nvidia.com>
Cc: Tom Rini <trini@konsulko.com>
Tested-by: Jagan Teki <jteki@openedev.com>
Signed-off-by: Jagan Teki <jteki@openedev.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>