net: pfe_eth: read PFE ESBC header flash with spi_flash_read API

net: pfe_eth: read PFE ESBC header flash with spi_flash_read API

Read PFE ESBC header flash with spi_flash_read API
- logs as follows,
  Net:   SF: Detected s25fs512s with page size 256 Bytes, erase size 256
  KiB, total 64 MiB
  "Synchronous Abort" handler, esr 0x96000210
  elr: 000000008206db44 lr : 0000000082004ea0 (reloc)
  elr: 00000000b7ba6b44 lr : 00000000b7b3dea0
  x0 : 00000000b79407e8 x1 : 0000000040640000
  x2 : 0000000000000050 x3 : 0000000000000000
  x4 : 000000000000000a x5 : 0000000000000050
  x6 : 0000000000000366 x7 : 00000000b7942308
  x8 : 00000000b76407c0 x9 : 0000000000000008
  x10: 0000000000000044 x11: 00000000b7634d1c
  x12: 000000000000004f x13: 0000000000000044
  x14: 00000000b7634d98 x15: 00000000b76407c0
  x16: 0000000000000000 x17: 0000000000000000
  x18: 00000000b7636dd8 x19: 0000000000000000
  x20: 00000000b79407d0 x21: 00000000b79407e8
  x22: 0000000040640000 x23: 00000000b7634e58
  x24: 0000000000000000 x25: 0000000003800000
  x26: 00000000b7bdd000 x27: 0000000000000000
  x28: 0000000000000000 x29: 00000000b7634d10

  Code: d2800003 eb03005f 54000101 d65f03c0 (f8636826)
  Resetting CPU ...

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>