The ePOS EVM and EVM SK have QSPI as an option to boot. Add a qspiboot
target that utilizes QSPI for env and so forth as an example of best
practices. As QSPI is booted from directly we need to chang
CONFIG_SYS_TEXT_BASE.
Note that on ePOS EVM the QSPI and NAND are mutually exclusive choices
we need to handle that elsewhere, once NAND support is also added.
Signed-off-by: Sourav Poddar
Signed-off-by: Tom Rini