board: ti: am335x_evm: Remove duplicate setting of bd_ram_ofs member

With clang we get a report that we are setting this member twice.
Fortunately it is to the same value, so drop the hard-coded value line.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>