ram: k3-ddrss: Handle error properly in lpddr4_start

In lpddr4_start function error returned by lpddr4_enablepiinitiator
may go undetected due to overwrite of return code.
Add support to handle error in above case.

Reported-by: Andreas Dannenberg <dannenberg@ti.com>
Signed-off-by: Udit Kumar <u-kumar1@ti.com>
Reviewed-by: Bryan Brattlof <bb@ti.com>
1 file changed