The Hyperbus core expects that HyperFlash is always directly mapped for
both read and write, but in reality this may not always be the case, e.g.
Renesas RPC-IF has read only direct mapping. Move the code setting up the
direct mapping from the Hyperbus core to thh TI AM554 HBMC driver.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>