da850/omap-l138: Fix NAND flash timings

Though Commit id a3f88293 (da850evm:
setup the NAND flash timings) has configured the AEMIF timings, they
are not exactly in sync with the timings used in Linux. Linux is
configuring the timing register as 0x08222204, where as currently it
configured to 0x00100084 in U-Boot. This issue was found out when
support for NAND SPL is added in U-Boot. Without this patch U-Boot
does not come up with SPL.

Tested-by: Christian Riesch <christian.riesch@omicron.at>
Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Signed-off-by: Rajashekhara, Sudhakar <sudhakar.raj@ti.com>
Signed-off-by: Hadli, Manjunath <manjunath.hadli@ti.com>