sf: Cleanup spi_flash_info{}

sf: Cleanup spi_flash_info{}

- Proper tabs spaces
- Removed unnecessary
- Add comments in spi_flash_info members
- Add comments for spi_flash_info.flags

Cc: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: York Sun <york.sun@nxp.com>
Cc: Vignesh R <vigneshr@ti.com>
Cc: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Jagan Teki <jagan@openedev.com>
Reviewed-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>