Support for runtime detection of flash on OMAP3EVM

Hi all,

OMAP3EVM boards can have either Micron NAND or ONENAND flash mounted. The software needs to read settings on SW4 to check the type of flash and set
memory controller settings according to that.

After going through the UBoot code, I find that there is a #define
CONFIG_ENV_IS_IN_XXXX(NAND/ONENAND) which we set in the board configuration file.(this is a compile time option). Is there a way where in I can implement the runtime support ?